{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Introduction to Non-Personalized Recommenders"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## The recommendation problem\n",
    "\n",
    "Recommenders have been around since at least 1992. Today we see different flavours of recommenders, deployed across different verticals: \n",
    "\n",
    "- Amazon\n",
    "- Netflix\n",
    "- Facebook\n",
    "- Last.fm.\n",
    "\n",
    "What exactly do they do?\n",
    "\n",
    "### Definitions from the literature\n",
    "\n",
    "*In a typical recommender system people provide recommendations as inputs, which\n",
    "the system then aggregates and directs to appropriate recipients.* -- Resnick\n",
    "and Varian, 1997\n",
    "\n",
    "*Collaborative filtering simply means that people collaborate to help one\n",
    "another perform filtering by recording their reactions to documents they read.*\n",
    "-- Goldberg et al, 1992\n",
    "\n",
    "*In its most common formulation, the recommendation problem is reduced to the\n",
    "problem of estimating ratings for the items that have not been seen by a\n",
    "user. Intuitively, this estimation is usually based on the ratings given by this\n",
    "user to other items and on some other information [...] Once we can estimate\n",
    "ratings for the yet unrated items, we can recommend to the user the item(s) with\n",
    "the highest estimated rating(s).* -- Adomavicius and Tuzhilin, 2005\n",
    "\n",
    "*Driven by computer algorithms, recommenders help consumers\n",
    "by selecting products they will probably like and might buy\n",
    "based on their browsing, searches, purchases, and preferences.* -- Konstan and Riedl, 2012"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Notation\n",
    "\n",
    "- $U$ is the set of users in our domain. Its size is $|U|$.\n",
    "- $I$ is the set of items in our domain. Its size is $|I|$.\n",
    "- $I(u)$ is the set of items that user $u$ has rated.\n",
    "- $-I(u)$ is the complement of $I(u)$ i.e., the set of items not yet seen by user $u$.\n",
    "- $U(i)$ is the set of users that have rated item $i$.\n",
    "- $-U(i)$ is the complement of $U(i)$."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Goal of a recommendation system\n",
    "\n",
    "$ \\newcommand{\\argmax}{\\mathop{\\rm argmax}\\nolimits} \\forall{u \\in U},\\; i^* = \\argmax_{i \\in -I(u)} [S(u,i)] $\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Problem statement\n",
    "\n",
    "The recommendation problem in its most basic form is quite simple to define:\n",
    "\n",
    "```\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| user_id, movie_id | m_1 | m_2 | m_3 | m_4 | m_5 |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_1               | ?   | ?   | 4   | ?   | 1   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_2               | 3   | ?   | ?   | 2   | 2   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_3               | 3   | ?   | ?   | ?   | ?   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_4               | ?   | 1   | 2   | 1   | 1   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_5               | ?   | ?   | ?   | ?   | ?   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_6               | 2   | ?   | 2   | ?   | ?   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_7               | ?   | ?   | ?   | ?   | ?   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_8               | 3   | 1   | 5   | ?   | ?   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "| u_9               | ?   | ?   | ?   | ?   | 2   |\n",
    "|-------------------+-----+-----+-----+-----+-----|\n",
    "```\n",
    "\n",
    "*Given a partially filled matrix of ratings ($|U|x|I|$), estimate the missing values.*\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Challenges\n",
    "\n",
    "#### Availability of item metadata\n",
    "\n",
    "Content-based techniques are limited by the amount of metadata that is available\n",
    "to describe an item. There are domains in which feature extraction methods are\n",
    "expensive or time consuming, e.g., processing multimedia data such as graphics,\n",
    "audio/video streams. In the context of grocery items for example, it's often the\n",
    "case that item information is only partial or completely missing. Examples\n",
    "include:\n",
    "\n",
    "- Ingredients\n",
    "- Nutrition facts\n",
    "- Brand\n",
    "- Description\n",
    "- County of origin\n",
    "\n",
    "#### New user problem\n",
    "\n",
    "A user has to have rated a sufficient number of items before a recommender\n",
    "system can have a good idea of what their preferences are. In a content-based\n",
    "system, the aggregation function needs ratings to aggregate.\n",
    "\n",
    "#### New item problem\n",
    "\n",
    "Collaborative filters rely on an item being rated by many users to compute\n",
    "aggregates of those ratings. Think of this as the exact counterpart of the new\n",
    "user problem for content-based systems.\n",
    "\n",
    "#### Data sparsity\n",
    "\n",
    "When looking at the more general versions of content-based and collaborative\n",
    "systems, the success of the recommender system depends on the availability of a\n",
    "critical mass of user/item iteractions. We get a first glance at the data\n",
    "sparsity problem by quantifying the ratio of existing ratings vs $|U|x|I|$. A\n",
    "highly sparse matrix of interactions makes it difficult to compute similarities\n",
    "between users and items. As an example, for a user whose tastes are unusual\n",
    "compared to the rest of the population, there will not be any other users who\n",
    "are particularly similar, leading to poor recommendations.\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Flow chart: the big picture\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "image/png": "iVBORw0KGgoAAAANSUhEUgAAAvYAAAM2CAYAAACdfscgAACth0lEQVR42uy9d7AdxbW3ff+3XVBl\nrsu4bIOxjW1uvTbX5Cww0USBSSJIJBtjgsjBCJFzTkJCApFB5JxzDhJIJAMmmxyds+etp79vzdtn\nzo4n7n3O81StOmdP6JnpXt3zm57VPf9ViIiIiIhI1/NfZoGIiIiIiMJeREREREQU9iIiIiIiorAX\nERERERGFvYiIiIiIwl5ERERERBT2IiIiIiKisBcREREREYW9iIiIiIjCXkREREREFPYiIiIiIqKw\nFxERERERhb2IiIiIiMJeREREREQU9iIiIiIiorAXERERERGFvYiIiIiIwl5ERERERBT2IiIiIiKi\nsBcRERERke4R9v/1X/+laZqmaZqmaaPGFPaapmmapmmaprDvfGEvIiIiIjKiw2YU9iIiIiIiCnuF\nvYiIiIiIwl5hLyIiIiKisFfYi7TEIYccUneAzQ9/+MNi9913L5599lkzahD561//Wiy11FLFFlts\nUfz73/9ue/977rmneOeddwYkrcHwo7DBOqdOvOaRXndyn6vHlVde2dQnnnnmmWErPxGFvcJeZMSx\nyy67pHrwpS99qVhrrbV6WH4DfvLJJ82sQeLPf/5zsdhii/VJ2MyaNSuVzyOPPFKK3EUWWaRYaaWV\nin/9619D7kfDJeyH85pHW92p+lx/hX1//F9EFPYKe5GM3Xbbra74QDCddNJJaf24ceO86Q4S//jH\nP1IPb1+EzXXXXVcKpOAPf/hD8fvf/35Y/OjRRx8dljwczmsebXWnls81EvbNHmzIq776v4go7BX2\nIi2KE3j77bfT+vXXX79Hb+hrr71W7LrrrsWPf/zjZDvssEPx4osv9tp/7ty5xb777ltuN3HixF7b\nPf/8873Seu6558r1//znP4tJkyYVU6ZMKe699950Lmy37rrrFg8//HBaf8QRRxRf//rX0/LDDjus\n+NOf/tTvfVu91vwYTzzxRLHaaqslobLGGmsU5513Xi+xQhjDhhtumNJaZ511Ug8oPc5VYXPbbbcV\nO++8c3lctiU9jgfTp08vll122VQ+rD/jjDPSQ8Lhhx9eHH/88T3SaiePW7mGdv0opy/5tc0226Tz\n5npvuummYurUqcXee++dRCHp5dfcbvqt+vJQ150HHnggXfdXvvKVtB3+e+655xbHHntseZ0HHXRQ\n+TvPX5ZXfaCV43766afFMccck+pH+Bx5/be//a2uz/3nP/8ZFGHfyGfZ58ADD0zXGfUB7rvvvmKn\nnXYqrr322nIZ53fkkUembUUU9gp7kVEh7Ov1vp111lmlOImb7kMPPVTWn7j5x+/bb7+93BchEssR\nVyussEL5O27Q3IDrbXP11VenbeJVfSwn9AGxU32tz7nE/zxM9HffVq+1eoxqeoif4IorriiXb7LJ\nJj3OJRc2p5xySrl800037XFcRApwnvkxt99+++KPf/xjOpdcTPYljxtdQ3+F/UDlF/8jRCO9uOZ2\n0m/Vl4e67uTXPWHChPTgF7+r11l9cKi1vFU/JtY98nbrrbcut0FUI5Br+Vy9h74Q9s169msJ+2Y+\ny7ngD/x+9dVXy7QiPCrP8/fee6+sXyIKe4W9yKgQ9oiHadOmJdGDnXDCCT1upvQexs2fm3BViIRw\noOebsAh6vUNcXXPNNeV2F154YVpGr9onn3xSCjV6YQPSDXHx4Ycfpht/pDV58uQkVrixH3XUUeV2\n8+bNS/u+/PLLaRlC6C9/+Uu/9m31WvNj7L///sXf//73sqeZZfR+clwERlzvgw8+mLahJ3TPPffs\nIUYQq3FunFMwe/bsHunl4ilCYKoiibTazeNG19DMj0iPY1cNX+LtTZxjq/kV/kee5739ubCvXnOr\n6bdavkNdd3I/eeyxx8rr3muvvXr4Sb2e7uryVo9L7z2/99tvv3IbfIP6wAMxeV3L5+oR2yHMqe+5\ncQ30yPfHZyP9eDjN25zwDbj55pt7bCeisFfYi4x4YV/PCF94/PHHy+1feeWVHuIIi1fh0VtGr22I\nhOjpy0XHcccdl8JMELfVHvLg0EMPLQfoxY0/buhB3LCJZQ6iJ68q+vqyb6vXWu8Y1dh5HiDYh9lU\ncj766KNSELMdseKcX4h/4Nhvvvlmr5CdarhDVSSFeOtrHrca/9/Mj6oDfFs5FqFS8UCWQ/6QD42E\nfSvpt1q+Q113XnjhhZb8pFVh326d5Ri33HJLOl4cN/6v5XPNhH2r/tCuz7711ls92pioX2Hx4ME1\n8mDSbBYfEYW9wl5kxAj7yy67rHj99dfTzf20007rFaoRXH/99U0FHDf8OXPmpP+JCW5247/hhht6\nrYtX8YQzxI2fnsXohcuFEttUr6kq+vqyb6vXGsdAbBIKU09gRXhFNU8RWfTw5uEDQE8vvbTVWVby\n7ZoJ+3bzuNk1NPOju+++O72FoPe0aiEmWz3WJZdc0qPHu1kZVwVvs/RbLd+hrjtRZjNnzuyxfzx4\ntttj3+pxKR/GflRDmBiXwNu1vgp7HuJ5GPv44497WNUf2vVZth0zZkyq2/gc54lPxKw9Z555Znrz\nhh80e+MkorBX2IuMKGFfjYPNY1zzV+4htrADDjggDWDDGMjIAEb+Ej5y5513pm0IUahH9Jrff//9\ndUUBDwb5jT+/Obcj7Puyb6vX2qrAivQQOlXBNn78+B6CLQ/loLeRWGYGQ1Zj8ZsJ+77kcaNraOZH\nrcTYt3qsOL++CvtWy6NZ+Q513YntLrjggprHbFfYt3udPJwxaDcX+OQ1PeR9EfZPPfVUW/7Qqs8C\nA6T5zSBp6hBTnn7++edletH7X31IElHYK+xFRrSwr3WTjoFy9HhFrHG87iZ2uQqxwcSB00sWwrka\nTsCNm5leiLO96qqr0jbEu1c5/fTTe/WIVwVMu8K+3X1bvdZWBVa8xaheL73ZeYhNiBF66vPwAdZV\nj9OqsO9rHg+nsI9zr4biRCx1f4V9q+U71HUHkZoPks7PP5/vPX5Xe6Or27V6XPLyrrvuKnvn6QV/\n+umny0Gq0YPerrBvd1acVn0WInwoQujCV6phUvkAWxGFvcJeZFQKe270MRtHCHRilrmB5oNOgRjc\n2JYezNiO3mZihoMQLcztjWiN3sCXXnqph+iOwXPMnjNcwr7Va21VSEZMcHVQ7EUXXdQjxCZ6WPP4\nf2CqQZbTmx9hDM0Gz8YA1L7mcbvCPuKmOb+qhfhs9VgxiBIfiuuLqQubDZ5tJf1Wy3eo605+3Xnd\nufzyy2sOnmVZDETN/SS2a/W4MT99NbY9esWrwr7VwbPtCvtWfTb2jZl8IhQM8vAjevHzKTFFFPYK\ne5ERS7NBghFSk29z9tlnl8voIWMmkLjh5h/jCUGAMX1jzEST34CZMzuW8f+JJ57Ya1rHel+mbEWc\n92ffVq+13jFqLY/0EG3kSd6zGNtFLyTGYEFitceOHdsjLCIGheZhFrvvvns53WV+zP7kcatfBW3l\ny7MYM+O0c6x46Ile2Xzax3pl3JfyaObLQ113ZsyY0aPu5NNM5ucfg0nxJ8o295M8/KyV4+az0ZDX\n559/fppHPtKPUJyqzzWb7rKZsK9VLq34bBDbcu7vvvtuWhYP0bXquIjCXmEvMmLh9Xyjnkl6SGvN\nDc0UltX54InXrX7cKcJtcjGG4Mlh8GG+DSICYRPHil65euKcKTSr4jxCIPqzb9DsWusdo9Zy8pP4\n4DwtHngQUvl2iPlqvhG7HVNjhlhCwITYDWFT61z6msf1llehV7oVYR9vB9o5FqFJ+TVy3vxddNFF\ny1CofL9202/Vl4e67kQPfdhmm23WS9gjiglry7fDp3/+85/36Tp58GJAar4NeZb39Fd9Lh+UXkvY\ntzKPfV98NogQtzwkKQakV99miCjsFfYiUgduoh988EGa4aJRLDLziNPDzHb1vlLJNqRFfG8nvjZv\n9VpbhfjlmB2kWb6RJ/XyLchnnWmUXifncRVCMnhgQLhVrxVhWZ1FqJPKd6DrDtfcaOpRZp0hvXwW\noP4cF7HONp999lm/fK6/dJvPiijsFfYiIlJH2EevMLHmCDsEXry1qA6qHem0Ot5BRERhLyIiHUe9\nEB967OuFgIxU4k0Fg0Gdk11EFPYKexGRroPZVyZNmpR66plznRlPiC0fbRCOxZiVm266qWloloiI\nwl5ERERERGGvsBcRERERUdgr7EVEREREFPYKexERERERhb2IiIiIiMK+24W9pmmapmmapo0GU9hr\nmqZpmqZpmsLeUBwR/VdE3xX9V8RQHCuniP4r+q6I/iuisLdyihVURN8V0X9F31XYj1r+8pe/FO+/\n/37xzjvvFH/605/MEG8uIvquiP4r+q7Cvpt4+eWXi1133bXXQIt99923+OCDD8rt/vrXvxZLLbVU\nscUWWxT//ve/e/0eLO655570sCH6b195+OGHU7595StfKd59992a2+y///41Bxx96UtfKjbbbLPi\nyiuv7OHnN998c1o/c+ZMM7iLffeQQw6pO9jshz/8YbH77rsXzz77bEfmaaNzDxus9nmo2n/9d+Cp\n19ZRnnvuuWfx9NNPD/k9e7T5k8LeyjloXHPNNWWeIHoOOOCAYq+99uohahD+8Oc//7lYbLHFegj7\nRRZZpFhppZWKf/3rX4NyfrNmzUrn8cgjj1hY+m+f+M9//lPssssuZd5Nmzat5nb5NvWMh13SA4Q+\ny8466ywzuYt9N8qdtm6ttdbqYXnZP/nkkx177sMl7Ae7/dd/h89v+tqu9fWeXdUXorBXGPWBOXPm\nlDc0nrBDsMDf/va34sgjj0zrabj/+c9/poacHqy84v3hD38ofv/73w/aOV533XXpHJ555hkLTP/t\nE++9916PGxZihLCzKrvttlta/+ijj/Zah6jjwZf1c+fOVdiPIN+Ncq8l3GnzTjrppLR+3LhxHSc4\nGvnsUDDY7b/+O7R+g7i+4YYbymu9++67h+yeHfpi/fXX76FFRGGvMGoRKs4mm2yS8uKyyy5rWNEQ\nNPTaV4U9Yv/www8vjj/++B43vNdeey2F9vz4xz9OtsMOOxQvvvhiuZ79Jk2aVEyZMqV44oknitVW\nWy2lu8YaaxTnnXdemdb06dOLZZddNp0j6ZxxxhlWUP23bWbMmJHy7NZbby1OOeWU9P9dd93VlsCD\niRMn9livsB/5wh7efvvttB7BkfdMN2vnAh4EedMT2+FH1e2ef/75Xmk999xz/T73nFbb3YDOnm22\n2SadD+3wTTfdVEydOrXYe++9072g2v63m36r+af/Dr3PX3/99Wn9CiuskMo1uO2224qdd965LLN1\n1lknlW1sU+ueHSK92b6hLwh7xPfoUAy9ce+99/Y6x2bpwaefflocc8wxxbrrrltugw/TcdnNvqiw\nVxjVhF4Wei4R7Th/PfIKUBX28eosv+E99NBDZR5HRYrft99+e9krwH55Lyrbxv8h4LkZ5ttsv/32\niiP9t+1eIOI28fPPP/88Nda1RFp+s6vV08TNacMNN+zRy6WwH1nCvl4PI+UbPhPitJV2DhAksRyh\ni1CK3yHcr7322rrbXH311QMm7Fttd+GKK64ol9MBFG+rImSTe0a1/W8n/VbzT/8dHmHP5BlVfRCd\nItimm27ao8x4u1/vnk2daWXf0Be5nyHI43feAdlKevgjbX+ktfXWW5fbINzjgaMbfVFhrzCqSQgc\nKk7+hNtMJOXCvpbQj4qZV4ioOF//+tfTq1v2ixsAg3j+/ve/lz1EcU4hukI8DderZm8u3c3jjz9e\nxsYDfhrCiV7SWje7G2+8MT0EMHD8448/Ll566aU0gLI6+FZhP7KE/YQJE9L4CwQodsIJJ/QQ2Q88\n8EApGFpp5xBH0c4xlim48MIL07KddtopiaYQzfSIB6Qb/vbhhx82PXe2ox2uGucfoWOttrt56BrX\nBNEbnwv7WveDVtJvNf/03+ET9ohe3tZQ1h999FEq7yj7GHMHs2fPbnrPbnXfXNhzfqFL7rvvvtIv\nSKvV9ELj7LfffuU21CUeWAg/jofTbvRFhb3CqKGwbydutJmwf+WVV3pULCwqZwzWoSHJQ3zym9Y/\n/vGPXjH80Uh04sA1/bfzCb/LwxoiBpQZRWrd7BpZLtAU9iNL2NczQkl4QAxabeeijc17B6MdPe64\n41IoQQiIePDMOfTQQ5sOQmzFZ2P/VtvdmEFq8uTJPY5Vfctb737QLP1W80//HT5hX207KXtmAXvw\nwQfL9ZTbm2++mXyi0T271X1z/6lGEcQsPqTZanpR/0jvlltuSQ8owN/4v1t9UWGvMKoJlYPelXoD\nCfsi7CMur5Hlwp5j//GPf6ybvsJe/+0Pec8jvU8HHnhgsjFjxtTsDY2bHa9jmfINI4aTh196cKvT\nZCrsR5aw51X/66+/ngTBaaedVjccptV2LiYnOPfcc+seO3yIAYtVIkSnkX/FuTPIkbBJ3hJUrRrD\n3KzdveSSS3q8oager5mwb5Z+q/mn/w6fsI8yo8c6HxyNTzBrXnXGqDxMrd49u9m+ccy8979aF/I0\nm6WH30f4ZB5qQxz+J5980lZdtu1V2HcF8dq02aveU089NVUcenGaCfu4IWBMmxlCisFWDLLib61B\nuAp7/XcwOP/885s22hdccEGvm12rszko7EeWsK+Wex77nocCttrO3XnnnQ2nV4X4FsL9999f178a\nPRi0E2Pfarsbx+2rsG+Wfqv5p/8On7BHE1DOeVnnYWmEshA/z8Dp6pSq1Xt2q/uGn9SaPjUX9u2c\nC/DQS8dO3u5zXW+99VbX+qLCXmFUl3jVVA1JCPL4T17HNWvI582bV8ZX1uo9JQaOtwMKe/13sOH1\nfwycQrDlvZn05ETc76KLLpq2bVckKexHnrCvVe4xGJBe6Ii1bbWdi9f81faVto03QcTY8zaAbY46\n6qheaZ1++ulN/XEwhH08bFRDcWLMQH+Ffav5p/8On7BnJpkYB0IYWYSM0cmXf3iK8mx2z2513/yN\nT4zPqJ4PD9itpoePMvtZ9M5zD+DDWzEbIG/JutUXFfYKo7owxVPkB1/PDIEDDBxk2ql8BpFmDXn+\nlE+FCYhno7KGyOqLsHfwrP7bDky312hweD5QK3omFfYK+1qdG9F2hUBvtZ2L7ehRfOGFF3r5JiFe\nhHdFDyKDtAMeCvJOlWbnHnH0+HrVovez1XY3OnQ472h3EXfxXZP+CvtW80//HXyfr/oN930Gjce1\nxsDr6Nnmmw45TG9ZnRazes9udd+8Tb788svL7ag74XeI7VbTi7FU1fErTMcawr5bfVFhrzBqyEUX\nXdTjlRZzLOevrRp9ebbWl+LOPvvscl96fIhNjhtUDNSt94W5WsvzV2XMTKI40n/buXHV+0ZD3sCH\nX7Y7WEphPzJ8t1m5R0hNvk0r7VzuYxhT9NEzX/34T/RGYvx/4okn9pq6r9m5NzMEWjvtbn5foIcz\nRE6t6S4b3Q/qpd9q/um/g+vzjYzZm4IYiIoxqJs3TWPHju3hExHSW71nhzBvtm8+Q03MZpPXhQhp\na/Vc8ogDfJjQTOaqD11DKE63+qLCXmHUlMcee6xHxQjj9RTT/eU9L4Q35D00+e+AmUPyeY8x4tV4\nlVsrnXrpA5UvbiqkqTjSf1shQgaqA15z8K1cqMTMC9FL1YwIWaCnSLrXd6Pc6/XM0VsdQigfJNis\nnQuuuuqqXvG9PCzk8ACab4Pw4MNqzUQFbxFaEfYRStlquwuEPORtL+fDX8LXIqSylftBX+8T+u/g\n+3zVKCdizWu9JYqwsdyPiX1nkoH8obd6z6ZtbWXf8BPsoIMO6rE931Xoy7nQlsdkCfk15r3z3eiL\nCnuFUcsw+v39999Pr+P6G1fG69+YB3wgYtTy2R0UR/qv6LudQKvtHDHD9CKyXT71ZXUb0iImeDjb\nOsIdeGBgVp9qG4xgyx9uhir/9N/OIPwYH63nx/Xu2e3sC2zXSIu0kx4PF/jYZ599NiJ8UWFv5RQr\nqIi+Ky0L++gFJYwCcYZ4it7Q6qBa/VdEYW/lFNF/Rd+VDqVeiA899tWPB+m/Igp7K6eI/iv6rnQw\nzGoyadKk1FPPfN58zIcBjvqviL6rsBfRf0Xf1XdF/xVR2Fs5RfRf0XdF9F8Rhb2VU6ygIvquiP4r\n+q7CXkT/FdF3Rf/Vf0XfVdiL6L8i+q7ovyIKeyuniP4r+q6I/iuisLdyihVURN8V0X9F31XYi3hz\nEdF3RfRf0XcV9iL6r4i+K/qviMLeyimi/4q+K6L/iijsrZxiBRXRd0X0X9F3FfYi3lxE9F0R/Vf0\nXYW9iP4rou+K/iuisLdyiui/ou+K6L8iCnsrp1hBRfRdEf1XRGEv4s1FRN8V0X9F31XYi+i/Ivqu\n6L8iCnsrp4j+K/quiP4rorDv8sq5xBJLaB1o3lz0cX1c3xXpdv+1rRu97a/C3kqnKez1cX1c3xVR\n2GsKe4V9fyvdZ599pnWAKez1cX1c3xUZacLetm/0tb8K+2GudJ9++qnWAaaw18f1cX1XZKQJe9u+\n0df+KuytdFpW6aZNm1baTTfdpP/q4/q4wl4U9ra/Wte0vwr7Ya50n3zyidYBFuVBRctN/9XH9XGF\nvSjsbX+1bml/FfZWOk1hr4/r4/quiMJeU9gr7Ptb6T7++GOtA0xhr4/r4/quyEgT9rZ9o6/9Vdhb\n6TSFvT6uj+u7Igp7TWGvsLfSWem8uejj+rjCXhT2tr+awl5hX3z00UdaB5jCXh/Xx/VdkZEm7G37\nRl/7q7C30mkKe31cH9d3RRT2msJeYd/fSvfhhx9qHWAKe31cH9d3RUaasLftG33tr8LeSqcp7PVx\nfVzfFVHYawp7hb2VzkrnzUUf18cV9qKwt/3VFPYK++KDDz7QOsAU9vq4Pq7viow0YW/bN/raX4W9\nlU5T2Ovj+ri+K6Kw1xT2Cvv+Vrr3339f6wBT2Ovj+ri+KzLShL1t3+hrfxX2HVzp3njjjeLb3/52\n8Zvf/KbH8vPPP79Yc801i3fffberHPuRRx4pll122ZrnXW9dvvyBBx4oFl100eKdd94pHn300bpp\nKey9sWgKexGFve2vwl5h3xXCftq0acXyyy/fdcL+wQcfLBZbbLGa5/3kk0/WXJfv88orrxS33npr\n07QU9t5YNIW9iMLe9ldhr7Af8kr33nvv1bXXX389CfsXX3yxx/IQ9vRcI2yPOuqo8jqPPfbYtJzt\n7r777tTDzfItt9yyeOGFF9LyJ554olh77bWL8ePHFwsssEDx+OOPp+Vvv/12ehPAfvymh3yZZZZJ\nDxZx3JNOOin9f8stt/RIe968eWXa2267bXkOpB2/H3744STGY93ll1+ejo9tvfXW6dixLizf56mn\nniomTpzYK62XX365WHfddYvDDz+84XU3MoX98Pi4NnSmsBcZfcLetm/0tb8K+y4X9tdcc03xta99\nLYWm4CRcK73ac+fOTf+feOKJxZw5c5KIR6Qj3glvYR3LEOq//e1vy7R32mmn4sgjj0z/H3fccWm7\nu+66Kz1AcMwrr7yy3J+0Ee4bb7xxOk/S5mEgF+/571yMs5w0ZsyYUdx7771JiDcT9nla/M/58FZj\n6aWXLjbYYIN0/EbXrbD3xuKNRWEvorDXFPYK+0GrdAjmevbaa68lwfzSSy/1WD516tQkan/3u9+l\n/+nxvuKKK1KoytNPP1289dZbaflCCy1UPP/886nHndAV8oEHAMQy+9CTXT3m1VdfXQphesHZ57TT\nTktpxD5nnnlmKcLZhwcD1vFA8dBDDyXxzbmxLv+d/19NgzcAHDf2C6u3f1zDOuusk/KIa468qXfd\njfJaYT88Pq4NnSnsRUafsLftG33tr8K+w4U9IvW+++7rJexDfCNoCU+J61x//fWL2bNnp179WJZb\niG/SJf3qMZ977rkkmO+///4kos8999xi7NixKWwmhPjZZ59dHHLIIT3Okx73doU9bwYijeiZb0fY\nxzVxLTzUsH2j61bYe2PxxqKwF1HYawp7hf2wVLpXX301iVbCbfLl++67b7HDDjuk/+mhJ/acsB16\nvRG+iG6EM736iP94ALjhhhtSjzsCuVbvOIZwp6eenvCtttqqFPrk4fTp09M2pM266gMI4jlmruGY\nrIsHhFrCngeGSCPfrhVhz//01HN+Sy21VLHnnnuW51bvuhX23li8sSjsRRT2msJeYT9olQ4hXc8Q\nsMSIL7jggsXNN99cPPPMM6m3nuu56KKL0jYMlkVUI3B5EFhhhRWSsCcunu0uvfTSFId+6qmnpt8M\nco0ZZRC+tY57zjnnpG3pmeccEMpf/OIX08w1rL/tttvS+uuuuy4dk553zpFBrIS8sI6HEc6JfddY\nY410rPy4kcaNN96Y9vvZz35WbpefS75PiP/4Px5O7rjjjpQWDzaNrrtRXivsh8fHtaEzhb3I6BP2\ntn0DZ4Qdv/nmmx3f/irsO7zSESu+xRZb9AgrOeaYY0oBTBw54TexbrXVVkuCmnWE0cRyhDkDX0Ms\nRyhPrWOGOGdQK7+PPvrotH3u0Ij+SJse/dtvv718GNlvv/3KdSuvvHIPYZ8f9/TTT+9xXfWEfexT\n73+223///YtFFlkknWO961bYd+6NBZ/Dj/D3gWqE481UPT8fSGtWp3K74IIL0oD4RtsQfsebL944\ntZO2wl5E/63V/tIJR8dYNUyVmeNCMwxE2zVS21Q0BvlFHpKGwt7KWbfSIYRbMSol4ST0QtdaT4w5\nVl1OmAz74cCtHqudc6K3vZ3zaSeN/li7162wH14fp6FF2HODGSgfoCH/wQ9+kBrhgfavqvFg0sqx\nCJnjYZObUKPtWM/brIG8DoW9yOgT9lH/6W3m7f6dd96Zwnd5A0/bQscgYbED1XaNxDaVY5B3TC5C\nPnZ6+6uw7xJhrw2uKew7W9jTIMe3CXiDxdiSZutIMxpvGvWf/vSnxWGHHZZuGNtss03ZqDN9a/xm\n3U9+8pNit912S+mNGTOmeOyxx2qeE+Fe8R0GxpzwxinS5OaZn9Ozzz6blu+yyy7lgG+ulZ6mGMOy\n+OKLp3EqbMf3IPbYY4+ydymugwfVI444ovQL3qa1enNS2IuMbmHPW+1qRxpTTscb+VbbLt7QN2pD\n11prrfT9Gto2xPAmm2xSTJo0Ke1PuDDH6JY2lXxjHF9EAHAe9e451WsnXxT2o1DYxyBPbXhNYT+8\nPh7Cnsa61jry4Pjjj0+zIW200UbpBkUvSqN1hJItt9xyZcNMz1Qsp1HnRkb6+e9Ib7vttku9WnzX\nIdLLz+mee+5J2xH2FTccbkKkwaxUcU70inHD41sLpMF4EMajMD0tNxy2u/jii9N2PEywHW/l8nNi\nQHr8T1gZ+3Oe119/fdofP+1EH1fYi8K+c9pf3qDHZBz0WNPGIKRZtv3226dtWm27GMvWrA1l3xNO\nOCE9BPAbsctxQ7DHvt3QpvIbUT9r1qw0lq/Z/SiunVDp4Wh/FfYKe01h39HCnrEY0XPDb77rwLaU\nT6N1kSZfWc7Fed6oV3/HPhHGFekRr9/onDgeNxDSmDJlSrpZci2MGWCgN2VIGoSIcS6kTw/Stdde\nm/anF40B8ZFGfk75/6TN+Vx22WXpphEzYinsRfTfZsKedqQaY0/sOO0P27TadrXShkZbXut3vm83\ntKn5MVq559S6jynsFfZaH43K3KrQUdh3h7BnClNe4+Y3KHpzKJ9G66L3JF7TRu9Jo5tSdV2kxwxQ\n1ZvQ4Ycf3uP8Y7+YVapqnBPpcYPgOvHTgw8+uNcA8kY3IfbZfffdy+3XW2+91DOlsBfRf5sJe9oe\nZtfjNzPtcX0nn3xyuU2rbVezNjS+LRPrGnWsdEObmh+j0T2neu0K+1Eq7HnqCzvvvPNSjFi+rC92\n9913F9/97neTw/Y3rUbGU3O85mq2bSvXlp93O2mHxWw8VNh2r11h3xrcFPrj4/WMBjFmxamu48vH\n48aNK3/z8PbNb34zlU+jdfhQ3MiWXHLJMr6SV755/cDv8Bl8jX3Yn/CdPD1e41bPiVewue9GGqwj\nBIj0MXp76EViylXS45y4TmaW4hUwr7XZhjTC5zmP/Jzif244jz/+eLpxEOfJcm5knejjCntR2HdO\n+xttD+1QLKO3mmskXCbatVbarmZtaH7vrvU7tu2WNjXPu2b3nHq6RWE/CoU9s8MQw1VL2LRrpMFH\nmQZT1GPEl9WqoFVr9dry86bhaCXt/BhUrquuuipVtHavRWHf+vkwoHTmzJkDLuzxEeIkiZkkjpEe\nJRrS6FliEBZlS68OjTcDYhutw4fiNWzEXlKmvL7lf3yF9LlhrL766snXOA/W0SuDT5EefsX/+fnG\ncYnJ5Fgbb7xxmUZ8V4E4T/Y75ZRT0m8GWPHWgPT4kjPLYzAb58GgXdbxO/f//CbEVLdsM3fu3LQd\nA9EU9iKjw3/70/7WEva0KbQhdHwghFttuyIUplYbWhXuzX53Q5ua512je069a1PYjzJhj+jAfvnL\nX6bzxMFwHpybJ2KWbb755inuK7YNmzhxYnHhhReWv3E45qRFuDBohCdblvMxqDwtHJjKQaVhHdvw\nhIsI4tj85sn3uOOO63VMKlaMWueplTQaHafWtZ1//vnlqPUf/ehH6bzZjhHlcd4xHRX/U0moPFGW\nfBArjokR40bDFKPWOY96+UferLnmmmlwC+fA6z6WK+zbOx9s4YUXTh8A+/zzz1vy8UaWh83kxkAv\n1p9xxhk9vpsQPtNoHT4UA6z4zRebaZzpjd9nn33KfVZaaaXSj2mYSSP8if+pG7XOOT5+FpbXhfzV\nMT7JTYfl+DL1huVsQ52I7TgntqUe5Oee/89bL14Vxz6rrrpqWc+amcJepPuFfV/bX+6TIU7zdiFE\nOu1Rq20XorZeG1ptd5v97oY2tZp3rd5zhqv9Vdh3iLBHjPLUxwAOXh9xzghrBM+GG26YnAoxnjtK\n/nqK3zvssENy5HiFxXJeM0VavG6K0eSkxfZM/8e+Rx11VNqOnk0qCukyYj4/XnzVla/f8gSNcI6K\n1+g4+bXFiHIGtbDdrrvumraL12Zx3rmwpxeX/elN5fUb+9Ozn58br9CislNZ6uVfNGKcH+sZDKOw\nb/98iCOM/+eff/70kInf9FXYt2L0jtAr0u66ekZPD5Yvw++iTtHg9+eceLVLTCb5Umu/+D++Gt3f\nc1fYi4wOYT/Y7W+rbVdf2qGR0qa2e89R2I9CYR9zzOKQCPZ4BcU6nIenQsRr7ighphkJHtvwuikX\nxfS8x2smKgSxwuyD4EUwh6heZ511yoE0bEda1Sf76nkhruPptNFx8mtjTvDohaUSMeds/hRdS9iT\nNufDgwZCnOuuVtpW8y96ZKvXprBv/3x487LKKqv06GGZMGFCKrvBEPZDYTy88sBKneim81bYi4we\nYT9S29+RbAr7USTsEZ9YvOpBGDM6/Ne//nWPdYgNhHQswxC9vEJC+PJqjG0QuDFfK+KEdbVCHEhr\nzpw5ZagB2zOQht5twm2iJz4/Hq/JDj300PJ3iO9mx8mvjfM76KCDer1uI438vPP/2Sc+GIStu+66\n6QEhP7dW8490eQBhWb4/ZVHr/LXalkOejh8/vsd64kCrPt4NxsMmb5i66ZxbNX1c02x/teFrfxX2\no1TY09uNgCZWPl+HGK0KewwRTpw6Pe4nnXRSjw8xIIpJa9lll0093BgimR5zBDDCnf34UhrHYyBK\nxL4Tq1Y9Fmkh/ON3PBA0O05+bWeddVYKqyGUh20itr+RsOeNBDFypEPsPMtz4V4V9o3yj3TjeIqe\ngbmx4EeTJ08u5ptvvh7beGNR2GuaZvurKexHlbCP6ZuYEQbxSbgJc2ZzznwRjR5EeskRw4SZxPZh\nhJSwH/HlxKyzDLH8/e9/PwnsmA2EQbbEhCH++R0fYWD2D37Ty43YRZyTFjPeVI9FKAvbEufOuYwd\nOzaNOm92nPzaWP6tb30rXRdTd6222mppHeEy+XkTUhT/E//PNrxhYL/ll18+9frn58Zy0iXNOM9a\n+Zenm+9vKE7758ODYLWniHhPXgfnDVnVj9o1wq+IrexvOqPdDMURGTmhOEPV/mrd1/4q7DtE2COq\n6WWOEecI7XzUNQ5Qz2H22muvNPMLafA7pvkL8Rpz1cZocgaxxr4xvR896Pxm9hn2rSekiMHPG5IQ\n9o2Ok18b2+Sj1vfee+/yQSI/7/x/Hl4Iv8lfM9Ko1RP2/K6Xf9W8Udj37XyqsZ3M0MADVD5Dw0Dc\nWGLmBR7GeMPTKY10PT9qx6ZPn16+Oasa9Y+HbOp1f46hsBcZecJ+qNpf21eFvcK+H8I+F6j5//R2\nD4RTEY6Ck4f47481Oq9Gx8mvDbHebi8sPbfYQJzncIuebhf2YYsvvnjdOZX7e2OJD38wyDv3nU4w\nBoXXevPTzrXxQEs9qLU+3oBhPHwr7EXUDkPZ/tq+KuwV9n0U9ghgbfhNYd/e+fCFwJh9YbB8PP82\nAdOkEgIW3ybYdNNN09gLtqNh5rPhW221VfHlL385zXwUabCOeYl32WWXtN/KK6+cbhr19qt3DIww\nM7bDeAPF2yreIpAOafA/25FO/puxJnEtW2yxRQop23nnnctvO/D2qXrt2223XfpeA28seKvVjT6u\nsBeFffe2v62Y7Wtntr8Ke4W9prBvmYjfHAofZ6wJop6xGQx8Jh/4SiAN+wYbbJBCr+KLgqyjsT/2\n2GPTIO1II9YRi8pMSny7od5+8UXBWseILx8SSkZvDzenuPHceeedZagQx8x/x1duI01e/3Lz4UGF\ncR+XXHJJSj+/bsLJYqrY+AYEPU8Ke5HRrR2Gsv1txWxfFfZWzhqVLmaR0YbXFPad5+P5uAnGdkRD\nzzrEOz07iH8+bMb/9NRU04h1pJHvx+xI1f0aHaO6jp6npZZaKoWTkQ43Gv6PY8Zv9ovtWMeNiPmn\n82urnvOMGTPSOsLaGPDNTY5l3ebjCntR2I9sjWH72pntr8JeYa8p7DvSxxlPQQPMjYEpTA888MAe\n62iQQ9jzypVltW48+U0h9mPGpOp+jY7BDeSQQw6pmW6jGw9p7rTTTg2vLV/OjW3ttdfuFUvL9yro\neVLYi9j2dpKwt31V2Fs5h6jS4dg4f+68hDUw3WQ8FfenMudPyX2xc889t+bTNMaTNK/UNttss34d\nQ2E/coQ9DT+vWPN13DRC2Nfzx7i5MJ1qvh+vc6v7NToG63h1HOtuv/328ubCa2RuUHFjyNexH74c\ndY7X1cR1EvdZq0eJuNmYGYtXy8SXXn755WkZ56ywF7Ht7SRhb/uqsLdyViodDjkYFnPHX3XVVamC\nYbxuIi/425+0qRxULCpaX/anEeAhg8pXa33E4mG80husPMpNYd95Po4P0zjPnj07fZiMfGCGHJbz\nQZavfvWraQam+P5BLX/E79mPnh38jv2q302I/RodI9ZRn/jN4DVeHbMvPso6pnfluw3LLLNMuY4Y\nzjxNepdYxw2H8+ADc7w2jvM9+OCDy31jGTew5ZZbrpg4cWJX+bjCXhT2I1dj2L52bvursB/Bwh5R\nVBXPzNvK6zDE+eqrr16OWKfy8BT7ne98pxyxztNv7MeUWjFinafuqBykM27cuLKikE7+m4oaX7zk\n2FTMX/ziF+WIdURb9dwZsX7EEUek0erM0a+wV9jzm5tH5Ad+yM0gvl5Mz1A9Yc+24YP8z82g3n71\njoGdeOKJvb7hwL7cGPDTWL7iiiv2uHnwteVYh89TZ9iHehQfUovr5UY4derUXtfBl6C5CSrsRWx7\nO0nY274q7K2clUqHAw6GMSgEUcTXaHli5Qma0eZUpvPOOy9VOvIFEX700UeXs47wlVdGs6+//vpp\n/9iPdVQgetMR/3wxlpAZKjGVhf85bv47Pn4VafKkjbjny7BUoosuuiiln583YRfsQ+VkZDvb8XAy\nWPkUprDvDh+ncaZHp9Xteb2K3+GPrfpRo2M0WsfMCvF9hlr74du1lg+2bw+XjyvsRWE/cjWG7Wvn\ntr8K+xEs7Ksx9vHFOioAwh6RTw862xN7j1iPJ2QqF+uZI7a6jp59nsSpzDH1VAj7/Df7xXasY3op\nHioidrpWQ0DsfTxQUIl5iOALcgp7byx9MR5K8SEebjulgR8NNxaFvSjsR377a/uqsLdy1qh0iOXB\nMKaS+sY3vpHmAMd5GKCCmI/1DEhhPdvxm0EoBxxwQI/9qbCIeF6RTZo0qVwX4p3KTDrxf6Qbv0lz\nxx13rHluiPcnn3yyx3IeANZaa61eDyPrrrtuEvqDlVeYwr77fLwV4+GQN0TDeQ6dYgp7kdEn7G1f\nR1/7q7AfwcI+ZhSptR4BztfaQpAj3pmFpvpgEMKe0JxYx1N6iPd4Yg/hna9jv3hNx7qHH344xcoR\nM13r3GIgDjFxhO4Qr8+DCcsI8VHYe2PRFPYitr22v7a/CvtRK+yrveK5sM972vkgRIw8Z1/mlI34\n9liH4OY3I9YJzWHfEOMIcD4PjZCPdRGbH2nSe886BD0PDXxCmrCcOKdf//rX5b55Lz4j1vfYYw+F\nvTcWTWEvYttr+2v7q7DvXGGPcB0M4xUZwh6xXWs9c8HSY09PeywjdCYfsY6gj3UnnHBCj/AYBDj7\nIsKZJiqWr7DCCuU69jvjjDPKdYh5HgTYh0G0LGMO2Tjf733ve+mT0tVzPfvss9NDxmDlFaaw7z4f\n1zrbxxX2orC3/dWGvv1V2Fvpehg96/TKt7uOeWOxevsxSLfW8tEqehT2msJeRGFv+2v7q7AfYcKe\n3mtt+E1hr4/r4/quyEgT9rZ9o6/9Vdhb6TSFvT6uj+u7Igp7TWGvsLfSWem8uejj+rjCXhT2tr+a\nwl5hnwaZasNvCnt9XB/Xd0VGmrC37Rt97a/C3kqnKez1cX1c3xVR2GsKe4V9fysd87hrw28Ke31c\nH9d3RUaasLftG33tr8LeSqcp7PVxfVzfFVHYawp7hb2VzkrnzUUf18cV9qKwt/3VFPYK++L555/X\nOsAU9vq4Pq7viow0YW/bN/raX4W9lU5T2Ovj+ri+K6Kw1xT2Cvv+VrrnnntO6wBT2Ovj+ri+KzLS\nhL1t3+hrfxX2VjpNYa+P6+P6rojCXlPYK+ytdFY6by76uD6usBeFve2vprBX2BfPPvus1gGmsNfH\n9XF9V2SkCXvbvtHX/irsrXSawl4f18f1XRGFvaawV9j3t9LNmzdP6wBT2Ovj+ri+KzLShL1t3+hr\nfxX2VjpNYa+P6+P6rojCXlPYK+z7W+nmzp2rdYAp7PVxfVzfFRlpwt62b/S1vwp7K52msNfH9XF9\nV0RhrynsFfb9rXRaZ5nCXh/Xx/VdkZEi7LXR1/4q7K10msJeH9fH9V0RhX3HWZSD7a/Cvisr5+TJ\nk3sVuja8pv/q4/q4visKe9vf4bEoB9tfhb3CXlPY6+Oawl5E/1XYK+wV9sPDtGnTtA4yhb0+ro/r\nu6Kwt/0dPotysP1V2HtzEW8uIvquiP5rOZhnCnsR/VdE3xX9VywH80xhL6L/ir6r74r+K5aDwl6n\nENF/Rd8V0X8tB8tBYa9TiBVURN8V0X8tB/NMYS+i/4rou6L/6r+Wg3mmsBfRf0X0XdF/xXJQ2OsU\nIvqv6Lsi+q9YDgp7nUKsoCL6roj+azmYZwp7ERs1EX1XRP+1HMwzhb2I/iui74r+K5aDwl6nENF/\nRd8V0X/FclDY6xRiBRXRd0X0X8vBPFPYi9ioiei7Ivqv5WCeKexF9F8RfVf0X7EcFPY6hYj+K/qu\niP4rloPCXqcQK6iIviui/1oOorAXsVET0XdF9F/LwTxT2IvovyL6rui/Yjko7HUKEf1X9F0R/Vcs\nB4W9TiFWUBF9V0T/tRxEYS9ioyai74rov5aDeaawF9F/RfRd0X/FclDY6xQi+q/ouyL6r1gOCnud\nQqygIvquiP5rOYjCXsRGTUTfFdF/LQfzTGEvov+K6Lui/4rloLDXKURGm/8uscQSWgeaviui/1oO\n5pnCXkT/Vdgr7G17xbZXLAeFvU4hMlqF/WeffaZ1gCnsRfRfy8E8U9iL6L/9Evaffvqp1gGmsBfR\nfy0H80xhL6L/KuxHkLCfNm1aaTfddJO+K6L/Wg7mmcJeRP9tTdh/8sknWgdYlAdiPjd9V0T/tRzM\nM4W9iP6rsFfY2/aKba9YDgp7nUJktAj7jz/+WOsAU9iL6L+Wg3mmsBfRfxX2CnvbXrHtFctBYa9T\niCjsFdUKexHbXrEcFPY6hVhBu17Yf/TRR1oHmMJeRP+1HMwzhb2I/quwV9jb9optr1gOCnudQmS0\nC/sPP/xQ6wBT2Ivov5aDeaawF9F/FfYKe9tese0Vy0Fhr1OIKOwV1Qp7EdtesRwU9jqFWEG7Xth/\n8MEHWgeYwl5E/7UczDOFvYj+q7BX2Nv2im2vWA4Ke51CZLQL+/fff1/rAFPYi+i/loN5prAX0X8V\n9gp7216x7RXLQWGvU4go7BXVCnsR216xHBT2OoVYQbte2L/33ntaB5jCXkT/tRzMM4W9iP6rsFfY\n2/aKba9YDgp7nUJktAv7d999V+sAU9iL6L+Wg3mmsBfRfxX2CnvbXrHtFctBYa9TiCjsFdUKexHb\nXrEcFPY6hVhBu17Yv/POO3Xt1VdfLRZbbLHyesO23HLL4rnnnmu4b1/tvvvuKxZddNHirbfeGvC0\nH3zwwWKZZZYp3n777abbXnDBBcWLL77Y8rm2k3YtU9iL6L+Wg3mmsBfRfwdV2C+00ELFnXfeWcye\nPbt46qmnivvvv79Yf/31i7Fjx/ZZxDay3/zmN0nQDsZDw2OPPZYeVJqd9xtvvFF88YtfTOfS6rmS\nL62krbAX0X8tB/NMYS+i/w6KsP/d735X1377298WiyyySPHyyy/3WD5jxozUO/3mm2+m3wh/eq7J\nky222KJ49tlny21vvPHGYqmllkrrxo0bV66rt88TTzxR7LHHHqkXfK+99iouvvjiMq3bbrstpcFx\nGx0zt0svvbRYYIEFkm211VbFGmuskdJudA677LJLWsZDDW8m6L1nf5Ytvvjixa233trrXOmx/8EP\nfpD+R9wfccQRpZ8cffTR5THrmcJeRP+1HMwzhb2I/juowh5xe+2116YeaUJPLrvssrRs++23T9vM\nmTMn5cXxxx9fPPnkk8W2226bRD+93gjfWPfII48Uyy23XBLmjfbhGCGQTz/99LRPiOIdd9yx2Hff\nfRvun5//vffem7Y799xzi7vuuiuJ+BD2jdJA8C+44ILFrFmz0sME211yySVpu9122618qMnPNRf2\nV155Zdr/oYceKm644Ya0PyJdYS+i/1oO5pnCXsRGbdCEPb3L9eyVV15JYrUaY7///vunXny2mTJl\nShL69HY///zz6QGAbRC1CPOll146iWC2RejTA99onwceeCAdk30I/2E5gvqll15KveaI6Ub75+fP\n8UPI8xuhHOfTKI3XXnstval44YUX0jnzYMP+XPNFF11UppGfa/4/aXOuPAQRrkMI0+uvv94wrxX2\nIvqv5WCeKexF9N9BFfYI3GeeeSb9vvnmm9N1n3zyyeU255xzTi/hHz3UZ555ZrHzzjv3SrfRPrlA\nRpATz8/2iGt63BHIjfavCvvDDz+8/B296qTdKI24bkQ/xzv44IN7bMPDQiNhzz677757uf16662X\nHk4U9iL6b7fD/SDCEkVhb+UUK2gXCnsEblWU33HHHaV4JlyGEBYMUXvdddelffJQGralB57e/pNO\nOqnuPrlAZh9i5H/0ox8VP/3pT4tTTjml6TGrwn6jjTYqf99zzz1l2o3SiOumx57ed8JqCOVhG9Jo\n1mNPDz09/YQyIc5ZPmnSJIW9iP7b9cycOTOVAW2rKOytnGIF7TBhj+iuZ4SeIHDnzZtXLkMEr7DC\nCsWSSy6ZQlYQ+OQFITbMooP45vfTTz9d3H333en/q6++OqVF7/3qq69exq3X2ifEN8fheITJfPOb\n30yz1NDrzbJGx8zPP94wXH/99Wnqyo033jgdn7QbpUH4DMe8/PLL0/IYQEw+/OQnP0nr+J2fK6E8\n8f8xxxyTtpk7d27ajvyi179RXrcr7DmOba/Y9spQM2bMmFQGp556qpmhsLdyihW024U9Ru801z91\n6tT0m7+RJwjwK664otw2X4fYffjhhxvug0CmRzyEPbb33nunWWsiPKfZMXPj5pOH0YSwb5QGx2GQ\nb1wj5x3bMXiXbZk6Mz/X/H8eRgi/iX1WXXXVXnnYV2HPW4W4sdr2im2vDCWMcYoy6Gvngr6rsBfx\n5jKIwh4ROxBG+AphLDT29da1s09/j5kbDyj02LebBvvF/0x7Sc9+O+dHzz/WyraNhP3nn3+eXn8v\nvPDCPR5SbHvFtleGCtoh4urJ/wkTJpghCnsrp1hBR7Kw1/pntYT9eeedVxx66KHF/PPPX/ocM/ko\n7MW2V4YSOj5C1NMeIfJFYW/lFCuowl5rQdgzsJeQobx3ngHE559/fr/9z7ZXbHulVZgBh975yHdE\nPctEYW/lFCtohwr7mBVGG16jLAi1+T//5//0EPQbbrhh+tBWLf/TNE0bKmNsj3H1CnuFvVhBR7iw\nJ3adaR0V5/0X9l/+8pd73Ejnm2++Yo899kjTbCrsNU0baqOzgR57Bs2Kwl5hL1bQLhD2iMa+2j77\n7JPy4fvf/34S9/1JayAt5ppnsGtf05g+fXqarrLWOgbcLrvsssXmm2/er2PkFuVBXD299F/4whd6\n3GDHjx9f9twbiiO2vSL6rsJeRP8dMGHPjDFMA8kUkcz80imiHuMLszxs9FV0c21MackUlbXW33rr\nraUPMPXnQAr7GDhLvu600069ZsJZZZVVFPZi2yui7yrsRfTfgRP2fKAq5n+/5ZZbimuvvbb47ne/\nm5Ztttlm6curIbLXWGONYuutty4WWGCBHkKYdauttlrxq1/9Ku238sorp2X19qt3DOzCCy9M22Fb\nbrll+pAUwp50ttpqq1Lkk07+mzTjWpgrnw9U8SGtmHefgWLVa99+++2Lo446Kr2xYI79wRD2+XSX\nTHUZc9c73aXY9uq/ou8q7EX035rCnq/H9sX4UBKi/tJLLy1uuOGGlB98cZUPNW2wwQbFt771rfLr\nrKxDTB977LFpzvhII9YRZsIHn3bYYYe6+8VXZGsdI74iO2XKlNSbjvhH2BMedOedd5ahQhwz//3Q\nQw/1SJPwGsQ9DyoLLrhgcckll6T08+tG6LMPDwx8QZft6Nnvaz6GtfKBKuJc8xkqbHvFtldEYW/l\nFNF/+y3sX3rppSSsiUM/5ZRTyh5y1vExJwaCIv4R6PxPT3g1jVhHGvl+CNjqfo2OUV3HsqWWWiqJ\n97vvvruHsM9/s19sxzq+ikvveH5t1XOeMWNG+UDBF2Z5iCAufiiEfcBg275+IMa2V2x7RRT2Vk6R\nESrsEcN9sRdeeCEJ3Dlz5hSnnnpqceCBB/ZYh+BFYCOkCWlhWTWNENkMRs33u/LKK3vt1+gYJ598\ncnHIIYfUTLd6jPw3aRLH3uja8uU8AKy99tq9QmLWW2+9JPT7mpdYO8Letldse0X0XYW9iP47KMIe\nYU0IS74OUR7Cnl7xENZVYc92TJmZ70e4THW/RsdgHaE5se72228vxTthOjwAhPDO17Ef4TcIdtYR\nDkTcPG8JuDbCbvLz5U0C5X711Ven0B3i9S+//PK0jHNW2IvY9ooo7EWsoF0t7K+//vqUH7NmzUrL\nJ0+eXMaeV3vMq8Ke/U477bQ0sw77Idb5v7pfo2PEOgQ3v8eOHZtCc9g3xDgCfPbs2UnIxzpEfp4m\nvfesIwSH87j44otTWE6c76RJk8p981785ZZbrthzzz0V9iK2vSIKexEr6PAJe4RpX4z4coQ9Ypnf\nhLVEvhD7jthm+V133ZV63ukxr6aBeGdbziP2Y0Bqvf3qHQM78cQTe4THIMDZFxG+1157lctXXHHF\nch37nXXWWeU6xDwPAuzD2wGWERYU18uDxtSpU3tdxznnnFN89atf7XNeYgp7Ef1X9F2FvYj+OyzC\nvp7Yp8e81e0R78sss0wS2YS/9PcYjdYxGw9Wax299bWOT3oDmT8KexH9V/Rdhb2IN5dBE/b0Tg+X\nMTXld77znRR6M5zn0QmmsBfRf0XfVdiL6L9dK+zpQUe8jnZRr7AX0X9F31XYi+i//Rb2hMFow28K\nexH9V/Rdhb2I/quwV9jb9optr4jC3soporBXVCvsRWx7RRT2Vk6xgna9sGeedm34TWEvov+Kvquw\nF9F/FfYKe9tese0VUdhbOUVGu7Bnqklt+E1hL6L/ir6rsBfRfxX2CnvbXrHtFVHYWzlFFPaKaoW9\niG2viMLeyilW0K4X9i+++KLWAaawF9F/Rd9V2Ivovwp7hb1tr9j2iijsrZwio13Yv/DCC1oHmMJe\nRP8VfVdhL6L/KuwV9ra9YtsrorC3cooo7BXVCnsR214Rhb2VU6ygXS/sn3/+ea0DTGEvov+Kvquw\nF9F/FfYKe9tese0VUdhbOUVGu7B/7rnntA4whb2I/iv6rsJeRP9V2CvsbXvFtldEYW/lFFHYK6oV\n9iK2vSIKeyunWEG7Xtg/++yzWgeYwl5E/xV9V2Evov8q7BX2tr1i2yuisLdyiox2YT9v3jytA0xh\nL6L/ir6rsBfRfxX2CnvbXrHtFVHYWzlFRruwnzt3rtYBprAX0X9F31XYi+i/CnuFvW2v2PaKKOyt\nnCKjXdhrnWUKexH9V/Rdhb2I/jsqhX2UhcLetldse0UU9lZOEf33/2fy5Mm9hGWnW5RFt513q6bv\niui/ou8q7EX0X4W9wt62V2x7RRT2Vk6R0ei/06ZN6zqLsujGc29mCnsR/Vf0XYW9iP5rWYj5Jfqv\niMLeyimi/1oW5peI/iuisLdyihVULAvzS0T/FVHYi3hzEcvC/BLRf0XfVdiL6L+WhZhfov+KKOyt\nnCL6r2VhfonovyIKeyunWEHFsjC/RPRfEYW9iDcXsSzMLxH9V/Rdhb2I/mtZiPkl+q+Iwt7KKaL/\nWhbml4j+K6Kwt3KKFVQsC/NLRP8VUdiLWEHFsjC/RPRf0XcV9iL6r2VhRphfov+KKOytnCL6r2Vh\nfonovyIKeyunWEHFsjC/RPRfEYW9lVOsoGJZmF8i+q/ouwp7Ef3XsrAszC/Rf0UU9lZOEf3XsjC/\nRPRfEYW9lVOsoGaEZWF+iei/Igp7K6dYQcWyML9E9F/RdxX2IvqvWBbml+i/Igp7K6eI/mtZmF8i\n+q+Iwt7KKVZQ/deyML9E9F8Rhb2VU6ygYlmYXyL6r+i7CnsR/VcsC/NL9F8Rhb2VU0T/tSzML/NL\n9F8Rhb2VU0T/tSzMLxH9V0Rhb+UUK6hYFuaXiP4r+q7CXkT/FcvC/BL914wQfVdhL6L/WhZifon+\nK6Kwt3KK6L+Whfklov+KKOytnGIFFcvC/BLRf0XfVdiLeHMRy8L8Ev1X/xV9V2Evov9aFmJ+if4r\norC3corov5aF+SWi/4oo7K2cYgUVy8L8EtF/Rd9V2It4cxHLwvwS0X9F31XYi+i/loWYX6L/iijs\nrZwi+q9lYX6J6L8iCnsrp1hBxbIwv0T0XxGFvYg3F7EszC8R/Vf0XYW9iP5rWYj5JfqviMLeyimi\n/1oW5peI/iuisLdyihVULAvzS0T/FVHYi3hzEcvC/BLRf0XfVdiL6L+WhZhfov+KKOytnCL6r2Vh\nfonovyIKeyunWEHFsjC/RPRfEYW9iDcXsSzMLxH9V/Rdhb2I/mtZiPkl+q+Iwt7KKaL/Whbml4j+\nK6Kwt3KKFVQGm5kzZ5Z538wmTJhghum7ov+KKOytnCL6b6cy//zztyTs33jjDTNL3xX9V0Rhb+UU\n0X87lUMPPTTl/SqrrNJr3UILLWRvvb4r+q+Iwt7KKaL/dgOff/55mf+vv/56ufzee++1t17fFf1X\nRGFv5RTRf7sJeuTJ//Hjx5fL6MFn2ZgxY8wgfVf0XxGFvZVTRP/tBuiRjzL47LPPUs99/L7vvvvM\nIH1X9F8Rhb2VU0T/7RbomacMJk+enHru+X/hhRc2Y/Rd0X9FFPZWThH9t5ugZ54ymG+++cryYDpM\n0XdF/xVR2Fs5RfTfLoMe+igLpsEUfVf0XxGFvZVTRP/tQvIPVjENpnS/7y6xxBLaCDfbXrHtVdiL\nKI6kJvHBKqbBFIW9prAXUdh7cxEZdf6rwBh5omckCXtmO9JGlinsRd2gsBdR2CvsFfajUNh/+umn\n2ggzhb2oGxT2Igp7e0btzVTYawp7tYOoGxT2IvqvAmr0iB6FvdYNPs63J8JuuukmtYOoGxT2Ivqv\nAmpkip5p06aV1q7oGUnC/pNPPtFGmEXZ4te5qR1E3aCwF9F/FVCKHoW9prAXUdgrjET0XwWUwr6T\n/fLjjz/WRpgp7EXdoLAXUdgroBQ9CntNH1c7iLpBYS+i/yqgFPYKe01hL6KwVxiJKOw1hf2w+OVH\nH32kjTBT2Iu6QWEvorBXQCl6FPYDam+//XbxP//zP2VehG211VbFSy+9NGDHefzxx4tll122+OCD\nD4bEhx5++OHie9/7XvH+++8r7EUU9gojEYW9prDvDL/88MMPB83eeuutYqGFFiruvffeYt68ecXc\nuXOTKN5www2LTTbZJAnjgTgOaS622GIDll4ze/XVV4vbbrttSI7VF1PYi7pBYS+isO9iAaUNrehR\n2Lcu7L/97W8Xr7/+eo/lF1xwQephf++994qnnnqqGD9+fCnKn3zyyfI36zbddNPi0EMPTXm50kor\nFffdd1+v4zz22GM9hD0PEvSos8+4cePS24HY9pJLLin++7//O6373//93+Kuu+5KyznWOuusU0yY\nMCGtv/766+se++mnny722muvls5x1qxZKb0vfvGLxSmnnFJsscUWvfJDYS+isLdyihVUYa8p7Dte\n2NNjT/4+8sgjqWf9yiuvTMt22mmnmr3t+W9CbMjD7bbbLu2/7bbbFmuttVavnvlc2D/33HNpn5NP\nPjm9IUCo8xDx7rvvJsHNOsQ26yZOnFg+YMSx2B4BzsNBvWO3eo4PPfRQWnfuuecWDzzwQHrYQOS/\n/PLLCnsRhb3CXqygCntNYT+wfklc+mDZm2++mQRwNcb+oIMOSr3WbPPoo4+mbRDX1d8I9gUWWCD1\nuLMuBHxsG5bvg4jmweE3v/lN8corrySxzTGfeOKJ1NNOWbMPx7/ssstKYV/rWPWO3eo5Tpkypdh4\n443L8+TBIt92sExhL+oGhb2Iwr6LBZQ2tKJHYd+6sCcU5/nnn0+/77jjjpQnp59+ek1RXv3N/+z/\nzjvv1Ny2VhrTp0/v9SCB3X777SmdyZMn91i+5pprlsfigYBzjjTrHbvVc9x///2Lo446qjzP6kOA\nwl5EYa+wFyuowl5T2A+YXxIyMlj2xhtvJNFL73kso0edfLnnnnvS7wcffLBYdNFFkzDmNyErCGNC\nZ+htjzAa1vE71uXHyZefddZZxfLLL5/Sw373u9+l8uUcpk2bVnzta18r7r///rScY0X6tY5V79jV\n/+ttx7lsvfXW5XlyrQj7PD8GwxT2om5Q2Iso7LtYQGlDK3oU9n0X9gjeFVdcsVh66aWTuCZEhny6\n7rrrihdffDGJcnrRqwK6VWEfsfGXX355mm6TtwP8JvYeoc35cF6c0+qrr5566QnLaXas/DcCvZbI\nr25H7z3Hvvjii9Og4MUXX1xhL6KwVxiJFVRhrynsR4awx0LwzpgxI4WsHHDAAWV+rbLKKj2EfaNe\n9FzY58tJN9JjNpprrrkmLUdcI+RjHcdl/ezZs1vqsa/Vu99svxtuuKE8D2boIT944FDYiyjsFfZi\nBR1Fwh5RVGvgIeLghRde6DjBfNFFF6XZPhT23SXsEdadYMwNjw1UesTKE8uOwK6uw08R14N9TTxQ\nHHnkkeU58Js6TYjQYB5XYS/qBoW9iMK+wwQU4QH0Lt59991pNo85c+akmOANNtggzbQx2OKgHWNa\nQ3okEUydck6DKXoU9lorxpSa8RaCaTDztxQKexGFvcJerKCjTNjz2r7ai3n++ecXyyyzTIpP5jfC\nn8GH5NOWW26ZevNjW+KMielFdO+zzz7Fz3/+8/RAQFwzQiMeDpiLO/9dL016HpnlI8rl2GOPTfvs\nuuuu6TcPIsRJx/E5ztprr50+OMR5cJxG53vzzTen2GvWMegw1t1yyy099uErpgr7gfFLylQbPCO2\nn7dZM2fOTLPiDMUxFfaiblDYiyjsO0xAvfbaa0koM6iQnnoMoc6yHXbYIW3zzDPPpPw58cQTU5ww\nAhrRTw86M3+wjq988kEd9iN2OWYDISSA/0kn/90ozauvvjrNKkIc8Y033pi2Q3Tz9U6W8/Ehtotr\n4LhsQxonnXRSOad4rbSJf451CCAGUW611VZlGrF87Nix6YEnP85Qix6FvdbJprAXdYPCXkRh34HC\nvlaM/YEHHph68dlm6tSpSbAzTzgDFJmtg20YnHjmmWcmIU+POtsyj3f09PNFzFzY578bpck6et6v\nuOKK9PEfQoQQ2DFfecQ058Ke7el5b+V84/zY9qmnniouvfTSXtfx29/+NqV56623KuwV9n0y6k9f\nHwwV9iIKe4WRiMK+T8Iesfzss8+m37fddlvKi1NPPbXchnm5a32MB9GLID7kkEPKbXPx3kjYN0oT\nMTRx4sRy2frrr5963uNcQ8Dnx0TIs77Z+Z599tnFLrvs0isfWJ5fB2kRlqOwHxi/jPneWzUexngA\nY/Bpu/vWM77ISpniX/zmLRMhXYNxLD4aRbng73G8TjXe0HGuvBGLZTzYMm0mH9qqt5/CXtQNCnsR\nhX2HCSh6FRdZZJHUux3L6PEmP+688870+4wzzkghKwiU6Dlnej32Yd0aa6xR7ktoDmIGkcT/uZBC\nWMW6RmkygJeQGcQ18fDsg+iOc6UXvpEIbHa+rOPhgm15G8B0hKecckoKycnzhYcFQoD6IpYU9v3z\ny9yPBkrA4jeUAf8zGxRjQljGsXKf6K+RNr7D7DT4USeL+vi41vbbb18suOCCqY7we9NNN011jWtR\n2Iso7EUU9l0s7BFTK6ywQrHUUkslUUxPHvlDyAo3enrz+c3g0oixJ0af2WoYjIrQJ42YRxyBw+A+\nxFOsa5Qmg2URRuzD+XEuCHvCclg+a9asdF65sM9FYKO0ebiI8yXtX/7yl+mcEPD5cqYPROhwTQr7\n/vslYrGW0WtOyBPXQA8xb0hYTpn+4Ac/SA9m/KYsY4D2CSecUGy22WYpJIt1jMOIQc9bbLFFelhj\nOf631lprpQHb7HvttdcWe+yxR0qTtzYxEJuHR/5OmjSpPA8eaiONddZZJ+3Hug033DD5109+8pNy\njnp8Ma6Hnm7qTcwpTzqtnh9jQyId1m2zzTbl9bMufuPnRxxxRFn2Rx99dLkdx8uPxZu4ZsfCqFvk\nN+NRSI9teEtWr9wwhb2oGxT2Igr7YRJQ9QwhgrBHROfLIy6dsJZq6AyChQGssW019AWhHAJkv/32\nK5evvPLK5bpGaRIeQfhNrFt11VWTQCE9etVZdv311/c41xgcW+ucGp0vgg7Rw3K+GBrLETaEJbWb\nnwMpeka6sEeEcu6XXHJJekOz2267pXJEKOfCPr7yOmXKlHK2I8oHnw0/Pf7445NYZdBz9DTHOsQs\nDwM8NESaHJsHNx4S42EPUcsA7x133LFYbrnl0naRBjM93XPPPUn0x2DxCy+8MP3Pw21+XTwohM9x\nzFbPLx5UMM4pf7DJf5Mu504IWnyYCt/iTVcci/wkXfKz2bHCIp8x0h0KH1c7iLpBYS+i/w6gsG/H\nCI0hvh2BXV1HLzcPCYiXXJBEbyDWbpr19uNY/T3fWFcrbXrp+5tXCvuefkkZVI1pSulF53/ynOka\nmYYUYY/Axo/4n3EcG220Ubkfohxhz8Pe6aef3uNBEsHKOvIaMRvbsS5Pk/JHYOMDbIcQj+1idid8\nr5pGfi4ck7dJHCu/rjztds4vt/xcq795wGG/yy67LIUSMQCcaWtZznmTHm/g4m0aDwCNjhVGGXAM\ntiPNetuFKexF3aCwF1HYD4OAGkqjV5MeVXoJh/tchtMU9s39EjF68MEH93rbUxX2fBvh8MMPL/fL\nRSpCmxCaWIcYx//Ia9IIgV4VxyxDfJMGy/mf86mmX02jejw+5FYV9nna7Zxfq8Ke89x9993LPFtv\nvfVSD/0555xTc9B4s2OF7bzzzum62Y5Qo8gPhb2Iwl5EYT9KhT29lPSojmZRr7BvzS/pYSakhJh1\nRCQPhbV67On1HjduXLkfISN5j32+LsZhhJiN9OoJe/y1ul1V2OfrOF4u1AkZayTs2zm/3LjG/AGZ\nvIlzpzedtx28ISMdlnNOHIsQIvbByFPGjNS6jqoRWhRhRfGtB0J2FPYiCnsRK+goFvaawr6WX8YM\nRbmddtppSQATAsLAZnqJv/nNb6bfCEwEKwIVUco18jVkwmR+9KMfJeHNPsSzs46PmrEfPfs8LDBO\nI0+D44U45jchLByLqR6J28+343iRfjUNzpm3DHEN9JYzODa/Ls6D62r3/HIjfIb9rrrqqpQOgn31\n1VdP2x5zzDHp3OfOnZvSJByIc7rjjjvSPhdffHEKKWOmJ34zWLfRsXhQiC88xzIeEkLo1yo7TGEv\n6gaFvYjCfhgEVLcY8cfEJ3fzNQyk6OlU3+WrwQPhl4h0BGpcw7777pti3fnyL4KSHuYQogjjGAjN\nbC8I5/gAFOEu+aBnZjiKryLnaeS/6bmmJ519GDSdbxfCnt78ahpMl5oLe0JxGgn7ds4vN86P/Ij9\nVlpppVLYEz/PA0U+uDyOFVPVRl7xkbdGx+I4P/3pT1N6ed1j+cYbb5z2qVcnFfaiblDYiyjsFfY1\nLWbPoVeREAKFfef6LscbM2ZMMXPmzJb9EqFYz2Ja03rrEaeHHXZYKcj5HX4S2yCm6QVvdJxaxn7t\n7tMX6+v58WYBa2cd4T6E30R+DZYp7EXdoLAXUdgPsrAfCpEy0EasMD23TONHr303XsNgiJ5OFvZh\nCy+8cPpOwOeffz5ofhkx3/Ra850E/meg6Ejwk9Hu42oHUTco7EX03wEUUPTqEfcbecCHmaInlIF3\nSy65ZFq+5ZZbppheljOH/He/+920fPPNN08xuiwnLnjNNddMH9Ih5IBBiMwFn28baYQh5OMYhA6w\nfTvpRzqsQ/TFubMufje6xnrn1+hYCvv/9w2A+H/++ecvJk6cmPJ6MB44iRMnxn7GjBltl4WmsBdR\n2CvsxQo6KoQ9YQ0M5iOumDnF4+M08dXY4447LgkpBu8h7mNu7FjOlzgj3jnWIYZZn2/7+OOPp+XE\n7FbDLohRRtQzkBFh0Gr6xEBHGjEAMgR7/rveNUZPcK3za3Qshf3/OyZie5VVVunRiz9hwoT0QaXc\nL2OmFm3kmMJe1A0KexGF/SAL+3ZvzgwcpEear38yKC+m0SO8IgbOsR1CnynxWM4gvugJR/CyP0IZ\nMcf/9HpH2oTYMNiSwX3MSkI+I7Dzc8inB2wn/dyYHhAhH+eb/653jY3Or9GxWhU9teYUH0mWQ37z\n5dZ8PXH4CnuFvdpB1A0KexH9d4iEPQJ3t912K/Ng3XXXTbOSMN3dL37xi17bs/zXv/51+ZtQGkJZ\nEN6IO4Qyy1h39tln1xSEbJunyfYIe0R0O+m3KuzrXWOj82t0LIV97/rCg9jkyZOL+eabr8c24Zes\nHyyL+e950zLcabWz//Tp05PPD2beDKYp7EXdoLAXUdgPsrBv9+ZMCMojjzySZtcgpv773/9+cdBB\nB6U5sJdddtkkjNmOXm6m3+OjNUw3GPvHfODExVdFTaSBsMbomWfaQnrI83MgjW9961tpOfu0mn5u\nfOSIBwCOw28+ksW1sG2za6x1fv0VeKMlFIfY92pPPfH2hOPkvbqDKTAJ2Yqy7m9a+FF/0mp1f2bJ\nIfyMN0UKe7WDqBsU9iL674AI+6OOOioJ5zlz5iThu/zyyyfRizAmT5iphuU///nP0weEENj58kMP\nPTTFrzNlIWI4FzW33npr2vbCCy9MQuakk05KvxkMW0/YE2/favq5xUeMiKdHbCLYOV+2rXeNjc6v\n0bEU9v/fMaux9cyQQ3nlM+Q080sGwxLyxP58eIryD7E+duzYVE6so8wor9iPMmM/jLEfUdbV9BlT\nEYOzeWDENxodt1rutfbn3LbaaqtyG3wvflf3r3ecnXfeOS2LUDDmto9B3Jtttll5nrnxkE3+Rn4f\nccQRDc8zlufp8oAe+bvGGmukAeacH9fQyjko7EUU9iIK+w4W9vQYEpqSx0XHDX3KlCnlcgQIYoDl\n8VXK+OAON/N6YQh5GvRQXnbZZb3OIRf27aafi56999673G/FFVcsxV6r15ifnz32zY8Ztvjii9ed\n0z7ygfKpGkKS/Rm7wRuVXXbZpVhqqaXSm5MY74DwpBc8xDtvVuILq5QdYh8xGuvy9OPrrXyplcHQ\nPOwhehsdl0HXCHPSqrd/vA2K4+W/8/0bHYd1PLAy7oMPdcVx2I6HBLbjYTO/HnyTfQgTiw928Qaq\n3nlGHsZyPqZFPSPdWMex+OIsabZyDrkp7EXdoLAXUdgPsrCvdxNuZgwqxarLEd0I7upyPrZDL3or\naUcaiORWz6ed9Fu5jlausZ3za2ajQdhvtNFG5ew3ffFLBC1vZqJsmGEHMYkoRnh++ctfTg9grI+e\ncNYRQhUPbaxD3MZ+efpsly/neDyANDpuLszr7Z9vw/L8d/5/o+MwdgORTYw9X6aNN0r4IWmQv+Rt\nfj1sR55cdNFFaaA540QQ3vXOs5pP1Cf2J7+q+dvqOSjsRRT2Igr7LhD22sDaSBb2ET/fjl8iLquG\nuD3ggAN69P4jRKPnHOHLNmwbgpl1J598cnHIIYeU6eTr8vSZYWmnnXZq+7iRVr39q8fLf+f/NzoO\nsz1xfQhpRHWtwckI8Op5/+pXvyrX//SnP00ivt55svzAAw8sf3NM3m6QLueJkGcZ61o9h9wU9qJu\nUNiLKOwHWdjXuwlrQ2sjWdgPlF+eccYZKbSEcBpE6+23394jJCb+ryXsCSuJdNivlrBnuxgczW96\nuPfZZ5+0vNFx8+PU2p9yRCDTW149fr5/o+sLYU/veByH9DC2pacf0Z9fD1POEnbDvsTOcxyEe73z\n5PsLhOTkwh4xH8I+z99Wz0FhL6KwF1HYK+wV9gr7XoaYRNwiOBGQq666ahKehK006hWPAdzEmTN+\ngkG20ROep4+QZrtZs2alY9CrzXYMkm7luPX2j/h0Pqg2e/bscqB2rQeDeschlIb/L7744jS9KukR\nPkNYGDNP8ZuBrvn18MVk9mFwN2ny0TiEfb3zRMDny5mOlAcN8qyavzEeoNk5KOxFFPYiCvsRKuyj\nZ08hr7Bv5pcxpWhuxG8jVOMa9tprrzSAmUHaDJiNwZtsW/194okn9gpxiXW58RGyfAA4x2znuLX2\nRwyzT3WgNvvk+zc6DmnQmx4zQOXHYRsG1VavhXh4wm/yWYkQ+fXOMz40F8uJqeehqFZ+VtOodw65\nKexF3aCwF1HYD4OAateYxYP8uPnmm8tl9DD+8Ic/TNMPxrLNN9889QYOxDGrVkt4tGvTpk1LYqjW\nOnoll1lmmWLTTTft1zEGU/SMdGGfC1bKo908pueb3udm29FbXcsPWj1uvf2pE1iz/Rsdh2uoHgfR\n3yi9esetd56t5lM756CwF3WDwl5EYd8lwp6b+rbbblt89atfTaEG/N54441TWAGz1YRY4DfrB0PY\n0+NIqEBfRTfnSa9jPWHPQ0uUO1P9Kew73y+1zjKFvagbFPYiCvtBFlCI8IEwevgQ1sxnfdhhh6XX\n+MzAEesZEEiPN7G6xA7/8pe/THm40korleEKCObVV1+9GDduXNqf2OSrrrqq+M53vpO2/dnPfpYG\nBEaaTAfIdhhhCquttloK9SEd5jHn/5jjPP9NKAPXTpq8RXjyySfTB7X4/Y1vfCOFK1Svj5ldDj/8\n8BQeseeeew5YvoUp7AfHL7XOMYW9qBsU9iIK+y4SUPFl1ogDztchihnMR8gM6+nhR/hvv/32Zc9+\nrEPYH3300eUgQb4Eizhff/31y23jWMT50puO+A9hf9ttt6WHjBDy+e/44mykycMG4p4vfPLGgTm/\nST8/dwYyxhzdDBpkuwg/UNgr7DWFvYjC3sopVtCOEFAxXd1AGB/PQUDTg840e/lUeMzIgRjnq5us\nRyyzjun7+E1PfqyjB511DHgMsZ5vy+wm1XX07C+55JIpNpkvjXIe/M+6/Df7xXasQ+jPmDGjDBWK\n88qN2PuYrYRr5CHi3HPPHdC8U9gPnl8281nKdaiON5pNYS/qBoW9iMK+iwTUjjvumIQ34Sxjxowp\nBRNCnWV8ybIquhnUh1C+4oor0jq2YxnrmP6PD/ZE+rFtCPtJkyaV63goiHQbCXvS5Dyr507aiPd4\nqMgfStZaa61eH+JZd911U8++wr57hX3MVINvDGRZ9tfw1/zhsy82derUNJ6l1jrqZQwE788xFPYi\nCnsrp1hBR6iAolebPGGObKbni3AX1jH3NqE3IVpC5Ieg5jfhMlVBg3jfbLPNeohvtg1hT2hOrONt\nQIh3/ucBIMRavo79EDXR0084EAIPEVSrx543CRFaROgO8fuXXnppWsY5K+y7U9jzhgZfoizjQbJT\nDD/LH0z7cm1f+MIXar59wgg7Cz/AvxX2Igp7hZFYQUeIsEfg9tcIuyE/jjjiiHJZzBuO0GdgKqEr\nLEe8s5yec8Q9ve4h9Nn2e9/7XhLkbHvNNdekbRFfDM5lW+LbESyxjukz+b3hhhum0Bz2DTHOvNqP\nP/54EvKxLj6sE2nSe886hD3nwdSdCKO4DqbrjH1jGYKLjwztscceA5J/mMJ+4P2ykf34xz9O+YAA\nZiwHD24xSHuTTTZJD3xshy8x5zyDryNkLNLgf95M7bzzzuVAcER5vf3qHQM777zzyoHgjPnIfZk0\nwv+qv/H/uBYegvF3PjgVA8H5YFT12sePH58GuDMIfOLEiYOe1wPp42oHUTco7EX030EWUISqrLPO\nOj0EMeIXsY3oQGA88sgjpbBHvIQY4X/ENusQ9vTY5yKaB4D8gznXXnttuS6+dhkWYohjI1hi+Qor\nrNBDnJ9xxhnlOs4NscQ+CKr4QijbIfx50JgyZUqvaz777LPTQ4bCvjuFPWMyEPUXXnhh+ZDI4G58\nIQZp48/xIIqY5g0UD5GRRqzbZptt0luq7bbbru5+8fXbWseIh80zzzwz9abHQPAYJJ4/7Oa/Gcyd\np8kDLOKeBxV8s/qQijHjE/vwAIJ/xRS1CnsRhb3CXqygI0DYI2gH2xAT8T/hK0svvXSK882XNzIE\nNoKq3XXMXBMf+6m1H/H0tZYPRZ5UTWE/tH5J+M3CCy+cfJAHRKZgjYdC/ImHSMQ/D5v8T094NY1Y\nF34c+zHeo7pfo2NU19GzzwMudYT6gpDn/6g/8Zv9YjvWIfSnT5/e49qq50zsPet4Q0bd4CGCMLpu\n8XG1g6gbFPYi+u8wC/vcYmpKehKHQ0B3qinsh9YvmQ0HgYvwJmxsv/3267EOH0V0I6R5q8OyahpV\n0R37XXbZZb32a3QMBPrBBx/c44Eh0m0k7Elzhx12aHht+XIeHNZcc82aA8GHoj4q7EXdoLAXUdiP\nMGHPlJWECijmFfaN/BIROpiGHyJ+H3vsseL4449PM8Tk6xDl9JwT+kKvOMK3mgbrQrzn+xFaU92v\n0TFYt95665XrKHfEO/vGgzA97NV17Bdvv1jH1K3EzRNXz7XxRio/X94kRKgZ34zA+G4Dyzjnwc5z\nhb2oGxT2Igr7LhdQ2tCJHoV934Q9syzFYGuW03tO7DmhLBHTXkvY03vOfieddFIK4WI/xDr/V/dr\ndIxYh+Dm9wYbbJBCc9g3xDgCnK8uI+RjHf6Rp0nvPetietmZM2emsJw43wMPPLDcN5bxUMBA8N13\n311hL6KwV9iLFVRhrynsu1vY8xtxng/SRmxHr3y9HnuEfXUgOGVWb796x8COO+64HuExIcAR3sy+\nFMuXX375HuL89NNP7zEQnF549mEQLcsIC4rr5UGDQd/V62DQLg8ZCnsRhb3CXqygXS7sEQHa8JvC\nfvj9EvFLj3mr2yPe6UEnTIbwl/4eo9E6Zq7B6u1HPH2t5SPNx9UOom5Q2Ivovwp7hb3CfsCNqSm/\n/e1vp3AXfVhhL6Kwt3KKFVQBpSnsa/gloSadbvSg812FbjjXTjCFvagbFPYiCnsFlKJHYa/p42oH\nUTco7EX0XwWUwl5hrynsRRT2CiORUSDsGfinDb8p7PVLfVztIOoGhb2I/quAUvQo7DWFvYjCXmEk\norBXcCjsO88vmWlGG1mmsBd1g8JeRGGvgFL0KOw1fVztIOoGhb2I/quAUtgr7DWFvYjCXmEkMgqE\n/bx587QOMIW9fqmPqx1E3aCwF9F/FVCKHoW9prAXUdgrjERGu7CfO3eu1gGmsNcv9XG1g6gbFPYi\n+q8CStGjsNcU9iIKe4WRyGgX9lpnmcJeH9DH1Q6iblDYi+i/CiiFvcK+yyzKQx9XO4i6QWEvov8O\nKJMnT+5109WG1/Tdke2XUR76uNpB1A0KexH9VwGl6FHYK+wV9iIKe4WRiP7bk2nTpmkdZAr7ke+X\nUR76uNpB1A0KexH9V0TftTzMLxGFvZVTRP8VfVcsD/NLRGFv5RQrqBkh+q5YHuaXiMLeyilWUBF9\n1/KwPMwv0XcV9iL6r4i+a3mYXyIKeyuniP4r+q5YHuaXiMLeyilWUP1X9F2xPMwvEYW9lVOsoCL6\nrlge5pfouwp7Ef1XRN+1PMwvEYW9lVNE/xV9V9+1PMwvEYW9lVNE/xV9VywP80tEYW/lFCuoiL4r\nlof5Jfquwl5E/xXRdy0P88uMEH1XYS+i/4rou5aH+SWisLdyiui/ou+K5WF+iSjsrZxiBRXRd8Xy\nML9E31XYi3hzEdF3LQ/zy/wSfVdhL6L/iui7lof5JaKwt3KK6L+i74rlYX6JKOytnGIFFdF3xfIw\nv0TfVdiLeHMR0XctDzG/RN9V2IvovyL6ruVhfoko7K2cIvqv6LtieZhfIgp7K6dYQUX0XbE8zC8R\nhb2INxcRfdfyEPNL9F2FvYj+K6LvWh7ml4jC3sopov+KviuWh/klorC3cooVVETfFcvD/BJR2It4\ncxHRdy0PMb9E31XYi+i/Ivqu5WF+iSjsrZwi+q/ou2J5mF8iCnsrp1hBRfRdsTzMLxGFvYg3FxF9\n1/IQ80v0XYW9iP4rou9aHuaXiMLeyimi/4q+K5aH+SWisLdyihVURN8Vy8P8ElHYi3hzEdF3LQ8x\nv0TfVdiL6L8i+q7lYX6JKOytnCL6r+i7YnmYXyIKeyunWEFF9F2xPMwvEYW9iBVURN+1PMT8En1X\nYS+i/4rou5aH+SWisLdyiui/ou+K5WF+iSjsrZxiBRXRd8XyML9EFPZWTrGCiui7loflYX6Jvquw\nF9F/RfRdy8P8ElHYWzlF9F/Rd8XyML9EFPZWTrGC6r+i74rlYX6JKOytnGIFFdF3xfIwv0TfVdiL\n6L8i+q7lYX6JKOytnCL6r+i7MuTMnDmzzP9mNmHCBDNM/xV9V2Evov+K6Ludyvzzz9+SsH/jjTfM\nLP1X9F2FvYj+K6LvdiqHHnpoyv9VVlml17qFFlrI3nr9V/Rdhb2I/iui73YDn3/+eVkGr7/+ern8\n3nvvtbde/xV9V2Evov+K6LvdBD3ylMH48ePLZfTgs2zMmDFmkP4r+q7CXkT/FdF3uwF65KMcPvvs\ns9RzH7/vu+8+M0j/FX1XYS+i/4rou90CPfOUw+TJk1PPPf8vvPDCZoz+K/quwl5E/xXRd7sJeuYp\nh/nmm68sE6bDFP1X9F2FvYj+K6Lvdhn00Ed5MA2m6L+i7yrsRfRfEX23C8k/WMU0mKL/ir6rsBfR\nf0X03S4lPljFNJii/4q+q7AX0X9FRo3vLrHEEloHmv4rorC3cooVVETfVdgr7G17xbZXYS+i/4qM\nVmHP/O/a8JvCXkRhb+UUK6iIvtsvYf/pp59qHWAKexGFvZVTrKAi+q7CfgQJ+2nTppV200036b8i\nCnsRxZGIvtuasP/kk0+0DrAoD8R8bvqviMJeRHEkou8q7BX2tr1i26uwF9F/RUaLsP/444+1DjCF\nvYjC3sopVlARfVdhr7C37RXbXoW9iP4rorBXVCvsRRT23lxE9F/Rd7te2H/00UdaB5jCXkRhb+UU\nK6iIvquwV9jb9optr8JeRP8VGe3C/sMPP9Q6wBT2Igp7K6dYQUX0XYW9wt62V2x7FfYi+q+Iwl5R\nrbAXUdh7cxHRf0Xf7Xph/8EHH2gdYAp7EYW9lVOsoCL6rsJeYW/bK7a9CnsR/VdktAv7999/X+sA\nU9iLKOytnGIFFdF3h13Yv/HGG8Vii/3f9s481ooqT8B/TzRpE01GJ3HfO1EnPSAC2iIoaqPiaCsC\n7o3QaivaTNsqCoroBAFBUWlABUF2BIFhBwUUWQXZlMUdt15sdUz6n/6jJt/JnEq9++6977713vve\n9yUnUHvVqd+p+u55p875eZonMfXp0yf54IMPStrHtGnTkgMHDij2ir2IYm/hFAuoiLFbTrE//vjj\nkzfffDN5//33kx07diRvv/12ctVVVyXXXHNN8vXXXxfd/tChQ8nhhx+eHDx4ULFX7EUUewunWEBF\njN2GiP0333zT6PTpp58mJ598cvLxxx/XmD958uSkQ4cOyZdffhmm16xZk5x22mkh33r37h1q85n/\nu9/9Lszjx8Hq1auTm2++Ofnqq6/Css2bN6fTW7ZsSS677LLklltuSY466qhkwYIFya9//etk6NCh\nYfvzzz8//LjIPb/c7dhnoXMhLVmyJDn33HPDshtvvDFdtnTp0hrb7Nq1q0nyj6TYiyj2Fk6xgIoY\nuxUh9kj5woULQ039+vXrk9mzZ4d5/fr1C+vs3Lkz5NeoUaOS7du3B8lG+qmtR7L/7d/+LZk3b17y\n1ltvhWY9UezZV5x+9913wz7YdvTo0WE7pm+99dZwXCS8e/fu6bYx5W63cePGgueybdu2dBk/ADp1\n6hT2G/cR5/OXCH7MsI1iL6LYWzhFjF8xdssu9jSTaWz65JNP8raxf+ihh0ItPutMmDAhiP7evXuT\nffv2BRFnHST7888/D5K8f//+5J133gn7opaf7bLTGzZsCDXu1KCzLN90dtuYctcrdi7PP/98+lcG\n1kX0Z8yYEebHHw3M/+ijj8I+ly1b1iR5qNiLKPYWTrGAihi7FSH2iPnu3bvD9PLly0PejB07Nl1n\n4sSJtcSfhBjH7RHvYmLP/xFy1o/L2O6LL76otW72/HK3K3YuL774YnLXXXfVukbmDxkypMY10yxH\nsRdR7C2cIsavGLutTuxjjXhWnmkzzzQ13jRroekKCRlftGhR2CZuT409TW8QZtZhu3Xr1tUQ+2xt\ner7pQmKfXa/YucRlsWaej4H5y8OYMWOSvn371rhmfiwo9iKKvYVTxPgVY7cixB6BbWyiuc1JJ50U\nmrbEeQhz586dk/bt24emNgg++UWzFnrRoTafaT5ApTccJHnOnDlps5j58+cne/bsCZJ9ySWXhP2x\nDHHn/xyjrumYcucXO5e1a9eG/7/xxhvhuu68885wfD6czc4fPnx4cswxx4QuOpsiDxV7EcXewikW\nUBFjtyLFnkRNOXk0adKkMM2/Md/o3nLu3LlhPjXpfKDKfD7AfeCBB9L1fvnLX9YQ+/iRaxT2YtNZ\nsc+dX+hccpfxg2PTpk1hPs1x4nza169YsaJJ8k+xF1HsLZxiARUxdhst9kh1SyaasNDkBcnOXcYP\nhPh/avFJ5TqXuCzfOVJL39TnotiLKPYWTrGAihi7VSX2JsVeRLG3cIoFVMTYbQaxjx+QmsqbFHsR\nxd7CKRZQEWNXsVfsffaKz17FXsT4FVHsq1eGaevOqLeKvc9e8dmr2IsYvyJtXuzpw70aU+w558wz\nzwxyX63XEZNiL6LYWzjFAipi7LY5sadnmuOOOy6ZN29eqLWvdqlX7EUUewunWEBFjN1Giz2DR9Un\nMaDTsGHD0utnoCZqzFnG4E3t2rUL83v37p3s3LkzzKdv+lNPPTXM79WrV7Jt27Ywn37uu3fvntx0\n002hX3j6m1++fHmNdeM+YmJ02ngM+p9n/frsP+6HZfSdH8+dZXG62DUWOr9ixyolKfYiir2FUyyg\nIsZui4r97Nmzw4ir69evTxYsWBDyYNGiRcnGjRvD/0eMGBGktmPHjkHu161bV2N+z549w2BW1LrH\nZcgwy7Prbt68Ocw/99xzw7rZc1i8eHGQ+lmzZgX5LXX/9Esf97FmzZq0GU/udKFr3Lp1a8HzK3Ys\nxV5EsbdwigVUxNitOLFn9FVqpGfMmBHkFdlFbJ999tkguVGUGa116tSpYf7FF18casGZ/+GHH4bt\nkXNkmP/v2rUr3TdNbKgF3717d/LWW2+FPM6t/f7oo4+CvO/Zs6de+8+mtWvX1hD77HShayx2fsWO\npdiLKPYWTrGAihi7zS72CHF9ElJ9zz33pNffo0ePIPHPPfdcMmDAgFrrM3/w4MHpNE1paMpCDThi\njCgzj2WIc9xvNrFudp+sj9gj2PXZfzaxDJFnhNnc6ULXWOz8ih2rlKTYiyj2Fk6xgIoYuy0q9lu2\nbAnNbhBY2rYjw4j12LFjk/POOy9to04tNz3XjBw5MjTJyYo3AhxlmFr+KNdxH9SOkxDs+fPnB4Ev\nJPZsU+r+s4mmN/wA4DhMr169OhX7uq4x3/kVO5ZiL6LYWzjFAipi7Da72CPi9UlPPvlkEOft27cn\n+/btSzp16pQ8/PDDyapVq0J+zJ07N8zv379/0q1btyDG2fmPPfZYaL9OM5o333wzOeOMM4Iks+9l\ny5aFdWnCQ283o0ePDtN8DJs9B/Zz4oknJu+//35oclPq/rOJ9vNsR3v6HTt2BGHnfFm30DUWO79i\nxyolKfYiir2FUyygIsZui4o9bchpmhKvv0uXLkGMWTZ+/Ph0PmJM23Pm01wmzqcdOsLKfGQ4fnwa\n95/dBx/Izpw5s9Y5ZMW+vvuPiZr1QYMGpdudf/75qdiXeo3Z8yt2LMVeRLG3cIoFVMTYrTixj4mP\nSkm582m+QtOUfDK+d+/ekvYd94F8l3o+9dl/KddRyjXW5/wUexHF3sIpFlARY7dZxR45NZU/KfYi\nir2FUyygIsauYq/Y++wVn72KvYjxK9LWxT728GIqb1LsRRR7C6dYQEWM3aoRe3qSoX26Iq/Yiyj2\nFk6xgIoYuxUo9nT/SF4sXbo0nUd3k2effXboJjLOu+GGG5I5c+Y0ixjTL3379u2TgwcPNngfkyZN\nCj3t5FvGDxK6xLz++usbdQzFXkSxt3CKBVTE2G0WsWeQpcYmRPfmm29Ojj766OS9994L09dcc03o\nkvLDDz8M69BjDdMsb4pj5qa1a9eGfuT5q0BDtuc86b6Sbi3zLV+yZEl6zxmMqqnPX7EXUewtnGIB\nFTF2yy72pN27dwex7tu3b/L4448nRx55ZPLuu++my5cvX5506NAh9Pd+0UUXJXfeeWfIvwsuuCBZ\nt25dKucXX3xx2AfbI9Cvv/56csopp4R1r7vuumTTpk3pPqdMmRLWI/HXAPqhR+zZT58+fVLJZz/Z\n6Xnz5oVrZ5+9evUKA0wNGDAg7X8/34+P2267LXniiSdC3/e///3vFXsRxd7CKWL8irFbWWJP7XpT\npTgyaxwJNrts2LBhyfDhw5PVq1eH5dTwb9iwIbn99tvTmv24DAl/6qmnkkWLFoVpRoLlB8GVV16Z\nrhuP9cILL4TadOS/a9euockMPyL4kcH/OXZ2Oo44G/fJjw3knhFs+YvDtGnTwv6z584ItGzDDwaa\nG7EeNftNmXeKvYhib+EUC6iIsVsxYs+IrQg0NehIe5xPTXnHjh2DYCPvLI9izEBPTNNGPi6jBp1l\no0ePDrLO9tl158+fX2sZNfu0sUfeV61aVUPss9NsF9djGaPjvvLKK2EgKn405BN22t7HHxRcIz8i\nXnrpJcVeRLG3cIoYv2LsVo7YI8ZNlfr16xfE+9hjj026dOkSZJn5W7duDfP4oHblypVBshkplmU0\n4UGUZ8+eHZaxHvNY9swzzyQPPvhguv+4LhI/atSo5NFHH02XRXlnv7nHyE6zT84z99zZN/LOuWbn\n8wPg0ksvTe93TD169Aii31R5p9iLKPYWTrGAihi7FSH2EydODPmxYsWKUAsem7uw7LXXXgtNb6Jk\nR8mPQs00tfksa9euXSrkyDu90GTlm3Wj2NM0Jy6jaU6Ud/7PD4Ao3tllbEfzG4SdZfxlgTbztKtH\n7Gl2k70u/pIQmxbRdIf2+jNmzAjzOGfFXkSxt3CKGL9i7LYasUeOyQs+Lo3zaPLCPGSdD1NpzhJr\n1pk/ZsyY0FPOkCFDgqzz/9ya9gULFoR1Z86cGaSedWP79rgM4Wb66quvDk1z2DbKOAK+ZcuWIPJx\nWWybH/dJ7T3LEHrOg647418aSIMHD063zdbi07Ro4MCBir2IYm/hFDF+xditDLFHUhubaKpy+eWX\nBzmP8xDhnj17Jr/4xS+CMNNDDvORd5rrMJ/84/98kMoyavupsaemPe6HpjMxr1kXoY/LRo4cWaN5\nDALOthz7vvvuS+d37tw5XcZ248aNS5dxbvwQYBs+omXerFmzwnq0pz/99NOT8ePH17rmF198MfzI\naIr8Iyn2Ioq9hVMsoCLGbtnFvq5EM5f4f+SdGnQkOzu/WKJmnVr5+i5jsClSoe34SDff/JbIE8Ve\nRLG3cIoFVMTYbVKxp6a6JVPsmpLa/ZY+diUnxV5EsbdwigVUxNitKrGnBp3+6ZV5xV5EsbdwigVU\nxNitYrE3KfYiir2FUyygIsZuM4g9bd1N5U+KvYhib+EUC6iIsavYK/Y+e8Vnr2IvYvyKtHWxp892\nU/mTYi+i2Fs4xQIqYuwq9oq9z17x2avYixi/Ioq9Uq3Yiyj2vlxEjF8xdqte7OlP3lT+pNiLKPYW\nTrGAihi7ir1i77NXfPYq9iLGr0hbF/s9e/aYKiAp9iKKvYVTLKAixq5ir9j77BWfvYq9iPErotgr\n1Yq9iGLvy0XE+BVjt+rFfvfu3aYKSIq9iGJv4RQLqIixq9gr9j57xWevYi9i/Iq0dbHftWuXqQKS\nYi+i2Fs4xQIqYuwq9oq9z17x2avYixi/Im1d7Hfu3GmqgKTYiyj2Fk6xgIoYu4q9Yu+zV3z2KvYi\nxq9IWxd7U2UlxV5EsbdwigVUxNhtk2If74Ni77NXfPYq9iLGr4ix+/8MHTq0llhWeor3odrOu9Rk\n/Ioo9iLKkYixq9gr9j57xWevYi9i/Iq0xdidOHFi1aV4H6rx3OtKir2IYi+iHIkYu94HMd/E2FXs\nRYxfEWPX+2C+iSj2Fk4R41eMXfE+mG8iir2FUyygIsaueB/MNxHFXsQC2uI4oE5lJmPXZ4iYb2Ls\nKvYixq9ir9j77PUZYr6JKPYWTpG2Kvbff/+9qQKSYu8zRMw3MXYVexHjt1Fi//e//91UAUmx9xki\n5psYu4q9iPGr2LcisW+JQX589voMMd9EFHsLp0grFPvvvvvOVAEp3g9kPpuMXZ8hYr6JsavYixi/\nir1i77PXZ4j5JqLYWzhF2orY/+1vfzNVQFLsfYaI+SbGrmIvYvwq9oq9z16fIeabiGJv4RRR7JVq\nxV58hphvIoq9hVMsoFUv9n/9619NFZAUe58hYr6JsavYixi/ir1i77PXZ4j5JqLYWzhF2rrY/+Uv\nfzFVQFLsfYaI+SbGrmIvYvwq9oq9z16fIeabiGJv4RRR7JVqxV58hphvIoq9hVMsoFUv9n/+859N\nFZAUe58hYr6JsavYixi/ir1i77PXZ4j5JqLYWzhF2rrYf/vtt6YKSIq9zxAx38TYVexFjN8WF/vP\nPvss+fnPf57mQUx9+vRJPvjgg2YR3/Xr1yennXZa8tVXXyn2Pnt9hphvZoQYu4q9iPHbVGJ//PHH\nJ2+++Wby/vvvJzt27Ejefvvt5Kqrrkquueaa5Ouvv25y8T148GCybNkya+yNXZ8h5pv5JsauYi9i\n/OYT+2+++abe6dNPP01OPvnk5OOPP64xf/LkyUmHDh2SL7/8MkyvWbMm1LKTT7179w61+XHdJUuW\nJOeee25YduONN6bLCm2zbdu25L777gs19oMGDUpmzJiR7mvlypVhHxy32DFj2rJlS3LZZZclt9xy\nS3LUUUclmzdvbtC5Ll26tMY2u3btalB+khR7nyFivomxq9iLGL9lEXtq7BcuXBhq6mkmM3v27DCv\nX79+YZ2dO3eG/Bk1alSyffv2INFI/6FDh4Kkx2VIdadOnYIwF9uGY9D8B7F//vnnwzb8n2Pdcccd\nyR//+Mei22fP/9133w3rsXz06NHJxo0b632ucR9xPn+p4MdO7rEUe/E+mG8iir2IL5cWEXuazdQ3\nffLJJ3nb2D/00EOhFp91JkyYEER/7969yb59+8IPANZBohHzWLPPusgzNfDFtnnnnXfCMdmG5j/M\nR8I/+uijUOuO+BfbPnv+GzZsCNtQ897Qc2V+9+7dw48L5sfzoLlQQ/JUsfcZIuabGLuKvYjxWxax\np3Z69+7dYXr58uUhL8aOHZuuM3HixFriT0J8X3zxxeSuu+6qtd9i22TFHpmmPT/r81cDmsN88cUX\nRbfPHod9IfJcR0PPlflDhgypkSech2Iv3gfzTUSxF7GAVp3YxxrvrByvXr06TMfmMjRNISHeixYt\nCttkm9KwLjXw1PaPGTOm4DZZsWebWbNmJf/+7/+e9OjRI3n22WfrPGau2Gdr4Rt6rn379q2RJ/xY\nUOzF+2C+iSj2IhbQsog9wlrfRHObk046KTRdifMQ4s6dOyft27dPPv/88yD45A/NVuhFh9p8pvnA\ndO3ateH/b7zxRtjXnXfemVxyySXJqlWrCm6zbt26IPYch+PRZAaRPvzww0OTHOYVO2b2/Glqk91X\nQ86VD2ez84cPH54cc8wxyYEDBxqUp4q9zxAx38TYVexFjN+KEHsSNeHkyaRJk8I0/8Z8QsDnzp2b\nrptdhqBv2rSp6DbIePygNe7jD3/4Q+iNJjbPqeuYWbHP3VdDzpXmOHE+7etXrFjRoPxU7H2GiPkm\nxq5iL2L8NlrskeLmTDRRoUkLEl1oWX22aewxm/pc+ZFDLX1j80mx9xki5psYu4q9iPFb0WJvUuzF\n+2C+iSj2Ir5cWkDs4wejpvImxd5niJhvYuwq9iLGr2Kv2PvsrTLiWAz07CTGrxi7ir2I8dvmxZ62\n7YyCq9j77K02pkyZEu7B1VdfbWYYv2LsKvYixm/TiD19tldjeuCBB0L+n3nmmUHuq/U6Yqqv2COG\nPnurly5duqSDuonxK8auYi9i/LZZsacnmuOOOy6ZN29eqLWvdqkvVex/+OGHIPQnnHBCo2LPZ295\niWMjkBg3QYxfMXYVexHjt0nEnsGk6pMQkWHDhqXXz8BM1JizjMGa2rVrF+bTv/zOnTvD/IULFyan\nnnpqmN+rV69k27ZtYT793nfv3j256aabQj/w9C+/fPnyGuvGfcS0f//+9Bj0N8/69dl/3A/Lbrzx\nxvTcWRani11jofMrdqxSUjGx53wee+yx5IgjjkjPSbGvTvhxRrt68v/WW281Q4xfMXYVexHjt3xi\nP3v27DDC6vr165MFCxaEPFi0aFGycePG8P8RI0YEqe3YsWOQe0aMzc7v2bNnGNyKWve4DBlmeXbd\nzZs3h/nnnntuWDd7DosXLw5SP2vWrCC/pe6ffujjPtasWZM248mdLnSNW7duLXh+xY7VULF/7rnn\ngvxlZf5nP/uZYl+l8AMtSj0/0pB8MX7F2FXsRYzfsok9o61SIz1jxowgr8guYvvss88GyY2izOis\nU6dODfMvvvjiIDXM//DDD8P2yDkyzP937dqV7psmNtSC7969O3nrrbdCHufWfn/00UdB3vfs2VOv\n/WcTzSGyYp+dLnSNxc6v2LHqK/aPPPJIctZZZ9UQeka8HTp0aPL9998r9lUGPeBkf6Ah9cwT41eM\nXcVexPhtUrFHiOuTkOp77rknvf4ePXoEiad2ecCAAbXWZ/7gwYPTaZrS0JSFGnDEGFFmHssQ56zM\nxsS62X2yPmKPYNdn/9nEMkSeEWVzpwtdY7HzK3asUhL3grbz//qv/1pj3+ecc04yefLkvLFnqr7E\nR7O2q9cdxNhV7EV8uVSE2G/ZsiU0u0FgaduODCPW9O5x3nnnpW3UqeWm55qRI0eGJjlZ8UaAowxT\nyx/lOu6D2nESgj1//vwg8IXEnm1K3X820fSGHwAch+nVq1enYl/XNeY7v2LHKlXsjzzyyOSwww6r\n0exmzJgxoZZesa/exA82auz5q5D47BVjV7EX8eXSbGKPiNcnPfnkk0Gct2/fnuzbty/p1KlT8vDD\nDyerVq0K+TF37twwv3///km3bt2CGGfn8xEo7ddpRvPmm28mZ5xxRpBk9r1s2bKwLk146O1m9OjR\nYZqPYbPnwH5OPPHE0JyBJjel7j+baD/PdrSn37FjRxB2zpd1C11jsfMrdqxSUrwfnM8dd9xRo+Ye\nwR84cGBYryliz2ev+OwVUewtnCKKfWhDTtOUbNMCxJhl48ePT+cjxrQ9Zz7NZeJ82qHTjpz5yHD8\n+DTuP7sPPpCdOXNmrXPIin199x8TNeuDBg1Ktzv//PNTsS/1GrPnV+xY9RH77Mez999/f9rfeUy3\n3HKLYi8+e41fMXYVexHjt/FiHxMflZJy59N8haYp+WR87969Je077gP5LvV86rP/Uq6jlGusz/k1\nROxjd5c04cjtHUexF5+9IsauYi9i/NYQe+TUVP5UygBVtMW/77770v7sffaKz14Rxd7CKWL8KvZV\nKPaROAKtz17x2Sui2Fs4RYzfVCRjDy+m8qb6iL3PXvHZa/yKsavYixi/ZRV7epKhfboir9iLGL9i\n7Cr2IsZvBYo93T+SF0uXLk3n0d3k2WefHbqJjPNuuOGGZM6cOc0ixvRL3759++TgwYMN3sekSZNC\nTzv5lvGDhC4xr7/++kYdQ7EXMX7F2FXsRXy5NIvYM8hSYxOie/PNNydHH3108t5774Xpa665JnRJ\n+eGHH4Z16LGGaZY3xTFzEz3H0I88fxVoyPacJ91X0q1lvuVLlixJ7zmDUTX1+Sv2IsavGLuKvYjx\nW3axJ+3evTuIdd++fZPHH388jKL67rvvpsuXL1+edOjQIfT3ftFFFyV33nlnyL8LLrggWbduXSrn\nF198cdgH2yPQr7/+enLKKaeEda+77rpk06ZN6T75gJT1SPw1gH7oEXv206dPn1Ty2U92et68eeHa\n2WevXr3CAFMDBgxI+9/P9+PjtttuS5544onQ9/3vf/97xV7EZ6+IYm/hFAtoZYk9tetNleLIrHEk\n2OyyYcOGJcOHD09Wr14dllPDv2HDhuT2229Pa/bjMiT8qaeeShYtWhSmGQmWHwRXXnllum481gsv\nvBBq05H/rl27hiYz/IjgRwb/59jZ6TjibNwnPzaQe0aw5S8O06ZNC/vPnjsj0LINPxhobsR61Ow3\nZd4p9iLGrxi7ir2I8VsxYs+IrQg0NehIe5xPTXnHjh2DYCPvLI9izEBPTNNGPi6jBp1lo0ePDrLO\n9tl158+fX2sZNfu0sUfeV61aVUPss9NsF9djGaPjvvLKK2EgKn405BN22t7HHxRcIz8iXnrpJcVe\nxGeviGJv4RQLaOWIPWLcVKlfv35BvI899tikS5cuQZaZv3Xr1jCPD2pXrlwZJJuRYllGEx5Eefbs\n2WEZ6zGPZc8880zy4IMPpvuP6yLxo0aNSh599NF0WZR39pt7jOw0++Q8c8+dfSPvnGt2Pj8ALr30\n0lqjvvbo0SOIflPlnWIvYvyKsavYixi/FSH2EydODPmxYsWKUAsem7uw7LXXXgtNb6JkR8mPQs00\ntfksa9euXSrkyDu90GTlm3Wj2NM0Jy6jaU6Ud/7PD4Ao3tllbEfzG4SdZfxlgTbztKtH7Gl2k70u\n/pIQmxbRdIf2+jNmzAjzOGfFXsRnr4hib+EUC2irEXvkmLzg49I4jyYvzEPW+TCV5iyxZp35Y8aM\nCT3lDBkyJMg6/8+taV+wYEFYd+bMmUHqWTe2b4/LEG6mr7766tA0h22jjCPgW7ZsCSIfl8W2+XGf\n1N6zDKHnPOi6M/6lgTR48OB022wtPk2LBg4cqNiL+OwVUewtnGIBrQyxR1Ibm2iqcvnllwc5j/MQ\n4Z49eya/+MUvgjDTQw7zkXea6zCf/OP/fJDKMmr7qbGnpj3uh6YzMa9ZF6GPy0aOHFmjeQwCzrYc\n+7777kvnd+7cOV3GduPGjUuXcW78EGAbPqJl3qxZs8J6tKc//fTTk/Hjx9e65hdffDH8yGiK/CMp\n9iLGrxi7ir2I8Vt2sa8r0cwl/h95pwYdyc7OL5aoWadWvr7LGGyKVGg7PtLNN78l8kSxFzF+xdhV\n7EWM3yYVe2qqWzLFrimp3W/pY1dyUuxFjF8xdhV7EeO3qsSeGnT6p1fmFXsR41eMXcVexPitYrE3\nKfYixq8Yu4q9iC+XZhB72rqbyp8UexHjV4xdxV7E+FXsFXufveKzV0Sxt3CKtHWxp892U/mTYi9i\n/Iqxq9iLGL+KvWLvs1d89ooo9hZOEcVeqVbsRXz2iij2Fk6xgFa92NOfvKn8SbEXMX7F2FXsRYxf\nxV6x99krPntFFHsLp0hbF/s9e/aYKiAp9iLGrxi7ir2I8avYK/Y+e8Vnr4hib+EUUeyVasVexGev\niGJv4RQLaNWL/e7du00VkBR7EeNXjF3FXsT4VewVe5+94rNXRLG3cIq0dbHftWuXqQKSYi9i/Iqx\nq9iLGL+KvWLvs1d89ooo9hZOkbYu9jt37jRVQFLsRYxfMXYVexHjV7FX7H32is9eEcXewinS1sXe\nVFlJsRcxfsXYVexFjN82KfbxPij2PnvFZ6+IYm/hFDF+/5+hQ4fWEstKT/E+VNt5l5qMXRHjV4xd\nxV7E+FXsFXufveKzV0Sxt3CKtMX4nThxYtWleB+q8dzrSoq9iPErxq5iL2L8eh/EPBPjV0Sxt3CK\nGL/eB/NMxPgVUewtnGIBFe+DeSZi/Ioo9iK+XMT7YJ6JGL9i7Cr2Isav90HMMzF+RRR7C6eI8et9\nMM9EjF8Rxd7CKRZQ8T6YZyLGr4hiL2IBFe+DeSZi/Iqxq9iLGL/eBzHPxPgVUewtnCLGr/fBPBMx\nfkUUewunWEDF+2CeiRi/Ioq9iAVUvA/mmYjxK8auYi9i/HofzAjzTIxfEcXewili/HofzDMR41dE\nsbdwigVUvA/mmYjxK6LYWzjFAireB/NMxPgVY1exFzF+vQ/eB/NMjF8Rxd7CKWL8eh/MMxHjV0Sx\nt3CKBdT49T6YZyLGr4hib+EUC6h4H8wzEeNXjF3FXsT4Fe+DeSbGr4hib+EUMX69D+aZiPErothb\nOEWMX++DeSZi/Ioo9hZOsYCK98E8EzF+xdhV7EWMX/E+mGdi/IoYu4q9iPHrfTDPzDMxfkUUewun\niPHrfTDPRIxfEcXewlk627ZtS956661kwoQJIfXv379eKW7HPtiXGL/eBzHPxPgVUewtnM3M/v37\nkxkzZgQhv+KKK5L/+I//aJbEvjkGx+KYYvx6H8wzEeNXRLG3cDaCn376Kcj1oEGDkgsvvDCvhPfq\n1SsZOHBgMm7cuJCWLVuWvP322yUl1o3bsQ/2le8YHJtz4Fw4JzF+vQ/mmYjxK6LYWzhLYPHixaHG\nPFewr7/++uThhx9O5syZk2zfvj353//932ZJ7JtjcCyOmXsenBvnKMav98E8EzF+RRR7C2cOX3/9\ndTJq1KhaNfO333578sorryQHDhxoNpGvK3FszoFzya3J55w5d/Hl4n0wz0SMXxHFvk0XTj5YpZlL\nVph/9atfJS+//HLy1VdfJT/++GNFJc6Jc+Mcs+fMNfjxrS8X74N5JmL8iij2ba5wUsudK/TUiC9Z\nsqTiZL5Q4lxza/G5Jmvwfbl4H8wzEeNXRLFv9YWTj0+HDh1aQ4Zpy07vM9Ui9LmJc+castfENfqh\nrS8X74N5JmL8iij2rbJw0ld8tg39vffem+zbty/54YcfWkXiWrimbBt8rtkC6svF+2CeiRi/Iop9\nqyic1Fxne7mhffratWtbjdDnJq4t2wafa2/Ltfe+XLwP5pmI8Sui2LeCwkkzlWwt/UsvvZQcOnQo\n+f7771t14hq51mztfVsd7MqXS8szZcqUNN/rSrfeeqsZZuyK8Sui2Fs4i5NtS08N9tatW1u90Ocm\nrjlbe0+eWEClJTjiiCNKEvvPPvvMzDJ2xfgVUewtnPnJbXrz0EMPJV988UXy97//vU0mrp08aKtN\nc3y5lIfHHnss5Dt/Lcrl+OOPt7be2BXjV0Sxt3DWLfW9e/cOAvvLX/4ymTlzZpsV+txEXpAn5A15\n1Fbk3pdLeeB7j5j3n376aTqfD7qtrTd2xfgVUewtnEXJtqdHYLds2aLQ5yTyJMp9W2l378ulfFAj\nT97fcsst6TzijnldunQxg4xdMX5FFHsLZ3Gpp005Avvdd9+Z8iTyJra7bwty78ulfFAjH/Ofbz6o\nuY/T9N4kxq4YvyKKvYWzBoy0GqX+uuuuSz7//HMFvo5EHpFXUe5b82i1vlzKCzXz5D8fblNzz/9P\nOOEEM8bYFeNXRLG3cNYk26YeUaWG8G9/+5uphEReRblvzW3ufbmUF2rmyf+f/exn6b2gO0wxdsX4\nFVHsLZx5pZ5243v27FHY65nIs9jmvlevXq1S7n25lB9q6ON9oBtMMXbF+BVR7C2cBaV+8+bNinoD\nE3nXmuXel0v5yQ5YRTeYYuyK8Sui2Fs4UwYNGpRK/aZNm5K//vWvpkYk8jDK/cCBAy2g0uTEAavo\nBlOMXTF+RRR7C2dg1KhR6WBLa9asUcybKJGXMV+ffvppC2iFEO+JqbKSsSti/Iqxq9g3ksWLF6cv\n1unTpyd/+ctfTE2YyNOYv2+88YYFVLE3KfYixq8Yu4p905Ptq/6JJ55QxJspkbfkcadOnZK9e/da\nQCtE7OkH3lT+pNiLGL9i7Cr2jST7sSyjWSrgzZvIY/L6iiuuCDJjAS2/2DtycmUkxV7E+BVjV7Fv\nJLFdPR947tq1K/nzn/9sasZEHsePaflQ2QKq2Jtqiv3EiRPT9D//8z/GrojxK8auYl8K27Ztq9Hu\nW/FumURex3yfP3++BbTMYu+IyZWR4v1A5rPJ2BUxfsXYVexLgOYgvEgfeOCB5NtvvzW1YCLPyXu+\nbWDaAqrYK/aKvYjxK8auYt8gJkyYkDbB+eijj5TtFk7keWySc9dddyX/+Mc/LKBlEnsHU6uMpNiL\nGL9i7Cr2DeDrr7+u0RTkm2++aZakwBdPCxYsSO/DjBkzLKCKvWKv2IsYv2LsKvb1Y+jQoWkvOM0l\n9abSUuwl58Ybb0wOHjzoy0WxV+wVexHjV4xdxb40srX1K1euVK7LnLgH8X48//zzVdUkp7WIvaMj\nV0ZS7EWMXzF2Fft6EmvradeN5JvKn7gX8S8oy5Yt8+Wi2Cv2ir2I8SvGrmJfnGxt/Y4dO5TqCknc\ni3hfxo0blxw6dMiXSwuKvQOnVUZS7EWMXzF2Fft6EAejoob4q6++MlVQirX2/Dtz5kxfLoq9Yq/Y\nixi/Yuwq9vn56aefQp/pvDiXL1+uTFdY4p5wbzp16hRG3KyGD2kVe5NiL+KzV0SxL0PhXLx4cXhp\nXn755Yp0hSbuDfdo+PDhyfTp05N//vOfvlxaQOwdDbkykmIvYvyKsavYl0jv3r3DS/PFF19Mvvzy\ny6KJwZPOPPPM9PxIZ511VjJ37tx0nbfeeis57bTTks8//7zO/eVLb7/9dtKhQ4fkiy++aND2LZGa\n4hynTJmSfPDBByWty73hHvXo0SN57bXXKr7WXrE3KfYiPntFFPsWLpzZj2b37dtXktgff/zxoZb/\nnXfeCYL73HPPhXOdPHlyWOfDDz8MyxsqvGvXrg0/HipZ7Ddu3Nioc/z000+Tww8/PORVKetzb+J9\nQuwrva19axF7B0urjKTYixi/Yuwq9iXAqKbxw0x6XKkrUVN80kknhZrm7HxqlBF+lm/evDm59957\nQ4094vvEE0+k1/Pkk0+G+e+++27SrVu35J577gnzaeOPLLOv9evXB2lmPaap2T7qqKPCeuecc06y\ndOnSMP/+++8P/bvHc3jzzTeTq6++OkhznFfsOCzr3r17ctNNN4X9b9iwIfwg4a8NrNurV69k+/bt\n6b5oAsN6pL59+yaXXHJJei3sI54v+8lOL1q0KGnfvn3YZ58+fZLdu3eH/GaaPGO6lLyPH9EOHjw4\nefXVVyu6hxzF3qTYi/jsFVHsW7hwDho0KG2GUx+xz5VRZBbhZT5NcaKY00TnmGOOCTX7CxcuDNfE\nC5lp/n/bbbcl27ZtS+64446wX6Q8K/arVq0K61FLvXXr1iDo5557bvLZZ58l48ePT7fhHP7rv/4r\nGThwYI3zKnacuAwJHzlyZLJixYow/fTTT4fr4UdCXJcfDSybNGlSOCfkP4p99no5ZnaaHznZfXbs\n2DHIPYNPkS+zZ8+u8UOkWIrNcfhRMX/+/Iru116xNyn2Ij57RRT7Fiyc9IYTX5jvvfdeo8QeSY5i\nnxVz5Jv5NB2hOQlyHaWa+bHmf//+/WGa5j3Z7bds2ZIsWLAgrHPgwIFk2rRpQexZtnPnzpBHbMN5\nUfuNdOc7r3zHyZ4zy2hShKzzV4bsughE7jLmxfPI/QtDdprt4nos43r4kfLJJ5/k/ctHscQ9ivdr\n3rx5YT+VOhptaxF7R0CujKTYixi/Yuwq9nVAzTIvy2uvvTYIaykJuUZId+3aVWM+NdpIMPPXrVsX\nxJZadQSWZjnxevj4E7nNrhP3e+qppwaJz92epifZj3UvvvjidDuay9AHP7XtnBfrZ8+rruMcd9xx\nYR7LGADqkUceqXGtrItAPPvss8njjz+eLovyzn5zj5GdZp+//e1vS87HuhL3invGXxhojkMbfV8u\nir1ib+yKGL9i7LZxsY+DUg0dOrTeYr93794a82nvTs00Yp0VW5rP0ByFGnXarzMfeY5Szce4cb9M\n82Mjuz3NT2iysnr16rDvNWvWpE1x2I6mPrS7R/Bpy597vnUdJ7sv5J1mMtlrZd0o9jTNics4j3iO\n/KjhBwB/ichdxnY0v4nfG/AXiz/+8Y/Jnj178uZjXYl7xT27++67Q9OmOXPm+HJpRrF39OPKSIq9\niPErxq5iXwf9+/cPL0vkEPEsJdE8BdmdNWtWqCVHLu+7775wrkg260SxRXSfeuqpsP77778ftmWQ\nJWrgkWq2oUYb6R42bFgq4LFXHLZHjBFgtqV2u2vXrmE9pjkWzXuQavZF05rc8y31OKy7ZMmSsO7r\nr78e9s+6/KiguUxc9sYbb4Tpa665JvzlINtWn+uneRAiH5fxgyS7zwEDBoRlCD3nQROljz/+uOT8\n517Fv7IgNtTaV2JzHMXepNiL+OwVUexbsHDGlyW16vUR+9x+7JF1PgKN6yDM1IQjttRMX3HFFem6\nF110UZBfhJumO+3atQvz+T8SnLs9beER4Lg9H8jSTSQ928TjDRkyJAg/Nfr5xL6U48T1+QEQj8W6\nCH1cNnbs2FpNgtiWmnnOK86/4IIL0mVs96c//SldxrVwTWzDXweYx4ewpeY/9yorOS+//HI4ji8X\nxV6xN3ZFjF8xdtuo2MeXJRJaqlQ2JlGzTsrKPzXbUf7r2p518tVsI8j8cOAj3Xzb1fc4JJrg0Ha9\nvstyrzGbaIrER7r59lffvOSexf7s+VFADzu+XJpH7B31uDKSYi9i/Iqxq9gXgbbevChvvvnmIMct\nnag1pwkNst7QfSxfvjzkEc1lkPbmOk6lJe4Z946/LiA39K/vy6XlxZ6Y+vnPf17jrzgkRnImHksR\n1vgBdDXKdhx9mR6bil1LU1yjYi9i/Iqxq9gXYcKECeFFSTOWcsgpNduIeWP2QQ04/crTy05zHqfS\nEveMe8cYBLE5znfffefLpRnEvpRRmOlilR/KNJPiL0RXXnll8p//+Z91jkpc39GHKy1lR4gudC1N\ndY2KvYjxK8auYl+E2CPOiBEjwsvXVD2JexZ7xqnUdvZtRez5sJvmVNn53A9qsmk2xXQc0Iz8uOGG\nG8IPUuZnRx/mQ3QGSos/BuJoxkzzPcmll14a/lLDdx98iM3H048++mjYvnPnzuEYueeXux37LHQu\n1LpnR4jmo/d47ELnRY19FPvstfDXingOufOzIztz/B07dij2IsaviGLfWGKPOLwcleXqStyzbM84\n9KzDXy18uTS92Nc1WBvCyncO1F7TheqMGTPCvNtvvz0dVCyOPEyNPlIcP9jOjj5Mk7FCoxcXGiEZ\nYee4jEQcR0HON+py3C5O5zuXQiNEFxtVOTsQW6GRlLPz2bbQyM51Dc6m2IsYv2LsKvYliD01aPQm\nk5vosrJ9+/ahVjLf8mx66aWXQneWxdbhBU9bd2SoPvtuylSu45aaSslHEvcsK/aV+AFtWxH73B6i\nSIxTQC0+6/BRN6JPzThdnMbuV+kZKTv6cLHRi3NHSM43nd0232jQdZ1LoRGii51X9v+FRlLOzi82\nsrNiL2L8irGr2DcCepIpJva8tM8444w6JZiXM21o6cKy2HosZ7RX/k9zgFL23dSp1GsqRyo1H7Ni\n361bt1RwJk6c6MulDGKPtPJjjOk41sEzzzyTrpPt6jSbuGdxe0S7LoFGyFk/LsvWdOduG1PudsXO\nhX1lR4jm+UCtfqlin72WfHnE/Oeffz40H8ouo1mOYi9i/Ioo9k0kLllhnDp1anLkkUeGRM8eiGOU\n4KVLl6YDQV133XXJ9u3bw/zf/va3af/stJel1pntmXf22WcnixYtCutRK/i73/0u7I+a8yjY9Czy\n2GOPpdfLoFD5xLvQfpELPlR8+OGH0z71OddSrimmYudAbXjsA582wfG6+ZGSzQ+awsTzoVaS5hEc\nk1rRQnmXTbn5WGj/MeWKDl1fFoOPbn251L98lDIKMwOnxXnUfHPdNJeJoxnH7lZJMXbYJjuKc7HR\ni3NHSM43HdfNHXU5d2TlQudSaITous4r/r/QiNTZ+cVGdq5rxGXFXsT4FWNXsS9BXJBaUmy3i5gs\nW7YsvMyRYF70mzZtSj+oo20s0kqTFmqZqaWkDS1iiWyz3pQpU8J6fDjHerzAaSqCzMemOPH/tElm\newRi3rx5YXtkI54XCTEutF/2xbIbb7wx/CUA+Y7nXeyasvsvdA6xTTLXTVvm8847L+w/HjPOv+qq\nq5ITTzwx5EdcRh7993//d9hnobzLnkM2H8mrQvuP6+eKDjX2+XrGYaTcLl26tPiDvq2KPZLLx6z8\nGIxN0MgH7iv3bcyYMWGaH280eYmjOMdmMcQf+4ujF+cKdD6RLyb22fnFzoVY5Vz4ixHXxTUg9vwg\nL+W8stfCdcdzyM6Pzwc+/uUYcWRnesxR7EWMXzF2FfsmFHuaD8TabKYRWwQUCaa/dF7OfAhIswM+\n9OPc+BiOFzfSyXwkYM6cOWF7esB45ZVX0n1kZT77f/ZNzfa0adOCONALR6701rVftqcWnOXZfRe7\npuz+C50D22fX5zwmT55ca780M2B7JDr3fIrlXfYcsvlYbP+FxD7b5eUPP/wQfgSdcMIJNZpc+HKp\nf/moaxTmKPa5ox1z7TR9yR15mOZWSG4cXC2OPozsFhq9OHeE5Lqm840AHecVOpdCI0QXG1U5u/9C\nIynnzi82snOxpNiLGL9i7Cr2JYgL8kgaPXp06B89TkdBpmYt+zLOJkSZP7EjpIgrcvrggw/WWAdB\nZR8Ibdxf9v9sQ7eNcf3LL788CHQ8D1Jd++X4rMO62X0Xu6bc/ec7B2o077jjjhrrkpj/0EMPpdPk\nwSmnnBLyg+Mj8sxjWbG8y+4zm4/F9h/n5RN7fpDQpOiII45Ij0Mba8W+ecS+PimOPIzoFht9uNjo\nxS1xLoWOX+p5FRpJOTu/2OjNir2I8SvGrmLfRGJPk484zaBOWUGmX25qKEm84OkeDwmNQsqf8+n1\n4uijjw7NXuLAULHJTCGxp19smrywH2r0mJ+VWlJd+43/zyf2ha4pu/9C5xCvGxFiPcSZ2kv6ke/V\nq1cN8Ubmo9hnz6dY3uUTe/KRbQrtP5/Y8+OBbwuyPxzOOeec8NeFcj3oFXtTUybFXsT4FWNXsa+H\n2Me+q2lLy5/g6WM61orH3j4QRWra6BObaT62oxkC0km7XeYjp4go4sqf81nGn/lp755P7BkUh3X4\neI/taMObK/aIbqH9ZveVK/bFrim7/0LnwA8BtqcPbuZTe8/2CHZ2/tChQ8MPD46Rez7F8i57Dtl8\npFlGof3niv1ZZ51VQ+h79uwZmvnkiyVT/RL525pGLK7mpNiLGL9i7Cr2JYg9tdExMRptVmy6du0a\naplZRld1cf5hhx0WBJT5CCwflDKfdY499th0vfvvvz+sS08xfNgaPxrN/p8a6l/96lfpNhdeeGEQ\n7Ox5Iaql7Jd1c6eLXVNMxc4he92cA+fC/PjhIYn27/yIyHf8YnmXTdl85HuCQvuPKd6/7LXRZnrg\nwIG1RqFV0hV7xV4xEuVIRLFvY2JPooaYmuHc+XEZH4UiofmWZUWZ2ul8+yiUqLEmFVunIfut65pK\nOYd43Q3db115Vygfi+0/3j8+JKaW/l/+5V9qSOktt9yS1tzbFKfh5cORjisjKfYixq8Yu4p9EejT\nnRclPa0gm6bqSdwz7l2PHj1SwaGP8MGDB9fqCYe/Pij2rVfs6U6VnmnoKYm/FtGlK021GrNPxozg\nB6ViL6IciSj2VVI4+/fvr9hXudhfe+21NfqxZxnQ1WXsu97uLlu32MdvOhB7/trE9x+N2R8xRJMu\n9qXYiyhHIop9lYn99OnTleUqS9yzYmIfoZ/xW2+9VbFvhNjnjhBczpRvFOTsKM7Z0Z2LjRZdbLTm\n7AjIlXTtir2I8SvGrmJfhAkTJoQXJaObxq4YTdWRuGfcu0GDBhUV+wgfHyL4vlyqV+zjCLCMEMsA\nWNlRkKPY0xQn/p9el+L6dOcaRzwmRuJoyIzWTI0/zfLigGgIPqPB8uNRsRdRjkQU+yoTe9plK8vV\nlbhnuWL/6quvpiPP+nJpOrHPjg5czlRoFORiIzoXGvG42GjN2RGQK+Xa8420rNiLGL9i7Cr2GbZt\n2xZelNTaxVElTdWRuGfcO+QtW2Ov2LdesR87dmwYRyF3fiGxz3axmk18n8F6yDs/EnP38cEHH4Rl\nUfoVexHlSESxr4LCyUudF+UFF1xQNUKLgND8APlgmlrIOE03mI888kiabwzqFNejD/hTTjklzKdd\n+qZNm9L90QSBpgjUYFZLPnDPuHeTJk1S7NuI2FNjT/MbmsswTQwzCjKjMecT+7h+/C6D8s6Ix7Fd\nfrb2P5/YW2OvGIlyJKLYV1nhjC9LPqZDjCs9MYrr6aefHvp3z52eOnVqGJ2VEW5nzpyZDvTEtfF/\nRpflY1Ikng8Qd+/enY4syzyWV0MecD35JIemOL5cmr5sZEcHLmcqNAryypUr05GOs6M7FxvxuNho\nzdkRkCvl2rMjLSv2IsavGLuKfQFizzjTpk2rCqmldjIr9tlpRmql1p0Bm2hmhAAj78xnxNiNGzcm\nW7ZsCduQrwgRssQ21H5Ww/WTuFe5PeKQEDhfLq1X7EkvvPBCmq/INz9UkfL4UWz2/7nr04UlH8RG\nkc+ul52m1j6OgKzYiyhHIop9FRXO+AEt3d5Vu9gj8bGrPtJll10WxIe2yfnaGtMsge2RfpodVIvY\nc69yP5ylG0R+qPhyaXqxr+8ox82dCo2C3NgRj4uNgFwJSbEXMX7F2FXs64AeMnhZ0qc1bWsrPfEi\nP/nkk4PEM7148eIg9nv27AldANKNH5JOcwXm/+EPf0hGjBgRRuZkGxJNDWbMmBFq8BF7rp/tq+H6\nSdwrzpmmFVFuaHrEXyN8ubR+sW+rSbEXMX7F2FXs6+Cnn35KX5hbt26teKmlVpo8oTkKfXMj7Bdd\ndFEQcz6Wpfad+Tt27AgfDiL29ALCNnxounPnztCvN9N0Fxhr/KtF7LlH8X7NmzcvlZuXX345jM7p\ny6Xpxd4B0SojKfYixq8Yu4p9CfDhKC/MP/3pT+HP75WcEPB77703zRtGzOzSpUuoieejQJrfxGX0\nHIPks122Oc5hhx0W2qMzn8F4uHa2r/RrJ3GPON8ePXrUkBvEvpJ6xFHsTYq9iM9eEcW+DIWTZim8\nMOlloxrklsTHsaT6LKOJDh/J8uOgWq4zN3GP4qBildwjjmJvUuxFfPaKKPZlKJxff/11+tKk1hvx\nNVVe4t7E+0RXhJX84WxrEntHOq6MpNiLGL9i7Cr2JRKb44wfP16JrtDEvcnXDAfJr7T29Yq9SbEX\n8dkrotiXqXDG5jj0uKJEV2aKveHka4bz448/+nJpJrGvltGIW3tS7EWMXzF2FfsSyfaOw4iVsWtI\nU2Uk7km+3nBIjK7ry0WxV+yNXRHjV4xdxT6F7iJ5cQ4cOFCZrrDEPeHe/OY3v6nVDId++X25KPaK\nvbErYvyKsavYp2TbsTLQE8JoKn/iXsT7Ql/81dAMpzWJfbWMSNzak2IvYvyKsavY15P+/fuHlyd9\nxSvVlZG4F9yTa6+9tobQLFy4MFmwYIEvF8VesTd2RYxfMXYV+9rQ/7u19pVZWz9u3LhatfWHDh3y\n5dLMYl8NIxK3haTYixi/Yuwq9g0g1tr369cv2blzp6mMiXuQr7aeNH36dF8uir1ib+yKGL9i7Cr2\nhckOWDV79mwFu0yJvM83IFX8aJbmCb5cFHvF3tgVMX7F2FXsizJq1KjwEu3evbuSXaZE3nMP7r77\n7loyg/T/85//9OXSAmK/d+9eUwUkxV7E+BVjV7FvIPRrf+GFF4YX6bBhwxTtFk7kOXnfqVOnWv3W\nU1tPF5i+XBR7xV6xFzF+xdhV7Eti8eLF6cuU/yvcLZOy+T58+PC8besrvba+NYm9ox5XRlLsRYxf\nMXYV+0YSP6SlWcjGjRsV72ZO5HFsgpPvg1lq6w8ePOjLRbFX7BV7EeNXjF3Fvn5km+TYS07L9YKT\nrwkO/dYvW7bMl4tir9gr9iLGrxi7in3DyPZtP3LkSAW8mRJ5W6jPetLLL7+cfPfdd75cWljs+Z7B\nVP6k2IsYv2LsKvZNxIQJE+wCs4W6thw0aFAteZk5c2ZVfDCr2JsUexGfvSKKfRUUToSTF+v555/v\nx7RN/LEseUre9u3bt5a40ARn0aJFVfHBbGsUe0dAroyk2IsYv2LsKvZNCO3te/fu7ce0zfSxbI8e\nPWq1qydNnTo1+fHHHy2gir1ir9iLGL9i7Cr2TSv38WPaq6++WrlvpNSTh4U+lo294Hz22WcW0DKK\nvbFaGUmxFzF+xdhV7JuB/fv3K/dNLPWTJk3K266e9Sygir1JsRcxfsXYVexbRO5tc9/wNvWFpH7u\n3LmhXb0FtPxib6qspNiLGL9i7Cr2zST3sc29cl9/qadNfT6p52NZxL7aPpZV7E2KvYjPXhHFvooL\nJ23ue/Xqpdw3QOrztalH6qv1Y9m28HIZOnRorXtmKm8ydkWMXzF2FftmlHv7uc/fT31bknrF3qTY\ni/jsFVHsq7RwZuWe9MILLyj0/5/Ii5gvhaSepjfTp09vNVLfWl8uEydONFVQUuxFjF8xdhX7ZpT7\nIUOGpBLbr1+/Nt1jDtdOHsT8+M1vflNQ6qtxACpfLuLLRcT4FVHsW3nhfPrpp0NvL3Egq7bY7p5r\njgNPkRd333133mYErVXqfbmIsSti/Ioo9q2kcO7duzfp2rVrWls9cuTINlF7zzVyrfG6u3Xrlrfn\nm9Yu9b5cxNgVMX5FFPtWVDi///775Lrrrkslt7XX3mdr6UnXXntt3qY3pJdffjlZuXJlq5V6Xy5i\n7IoYvyKKfSssnGPHjk06duyYCu+9996brFmzptUIPdfCNcXro+nN8OHD8wo9Pd+MHz++qkeU9eUi\nxq6I8Sui2Lfhwvnxxx+Hj0ej/NL1IzJczc1zOHeuIXZjSaItfaFa+vnz54fuLL/99lsLqIixK2L8\niij21cs//vGP0EXdlVdeWUvwq6kGP9bQZ4WeZjeF2tLHpje0pycPLKAixq6I8Sui2Fc9tCmnpnvY\nsGHJ5ZdfXmOo+D59+lR0//ecG+eYPWf6pR83blxBoecDWaSea27N7el9uYixK2L8iij2bbRwMhAT\n0vvkk0/WaKITP7J98MEHK2IEW86Bc8l+FBv7pC8m9KRXX301XGNrGnTK+BVjV8T4FVHsLZx5OXjw\nYDJ58uRkxIgRyaBBg0L3kFmBprkLgzxRW94SzXU4BsfimNmmNrHrSs6xWJOb2OyGa+LaLKC+XMTY\nFTF+RRT7NlM4aaLy3nvvBWGmlhvJp0Y8V/Kj6NMchlp0+ounRr0hws82bMs+2Bf7zBX5KPOcC+sV\nk3l6u+HcuQaupa01u/HlIsauiPErothbOFP4sHTHjh1BjvnIll5k+P/gwYPDx6n5RL+pE8fgWByz\nrpr52NMN58q6nHtb+jjW+BVjV8T4FVHsLZxFobabZiwzZ84M7dipCY8ijUBTe06TmL59+wYJp9/4\n+go827At+2Bf7LMUkc+2n+fcOEfO1Rp641eMXRHjV0Sxt3AW4bvvvku2bNkSBnWi7TpCTS15qQLe\nVIljcmzOgXPhnDg3MX7F2BUxfkUUewtnPWFgJ4R6zpw5ofkLCdGm1rypRZ59su94HI7JsdvK4FLG\nrxi7xq4YvyKKvYWzRaALSSSbD1VXrlwZ5Jua9CjiDU1xH+yTfXOMttpdpfErxq6I8Sui2Fs4ywIf\nrtI85tChQ8mBAwfqldiGbf341fgVMXbF+BVR7C2cIsavGLsixq+IYm/hFAuoiLErYvyKsavYi/hy\nETF2xfg1fsXYVexFjF8RY1eMXxHF3sIpYvyKsSti/Ioo9hZOsYCKGLsixq8Yu4q9iC8XEWNXxPgV\nY1exFzF+RYxdMX5FFHsLp4jxK8auiPErothbOMUCKmLsihi/Ioq9iC8XEWNXxPgVY1exFzF+RYxd\nMX5FFPsWvECTyWQymUwmk6ktJMXeZDKZTCaTyWRS7CtX7EVERERERLEXEREREVHsRUREREREsRcR\nEREREcVeREREREQUexERERERxV5ERERERBR7ERERERFR7EVERERERLEXERERERHFXkREREREsRcR\nEREREcVeREREREQUexERERERUexFRERERBR7ERERERFR7EVERERERLEXERERERHFXkRERESk9fF/\nYPl9GgY8LikAAAAASUVORK5CYII=\n",
      "text/plain": [
       "<IPython.core.display.Image object>"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "from IPython.core.display import Image \n",
    "Image(filename='/Users/chengjun/GitHub/cjc2016/figure/recsys_arch.png')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## The CourseTalk dataset: loading and first look\n",
    "\n",
    "Loading of the CourseTalk database.\n",
    "\n",
    "The CourseTalk data is spread across three files. Using the `pd.read_table`\n",
    "method we load each file:\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>user_id</th>\n",
       "      <th>course_id</th>\n",
       "      <th>rating</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>3</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>4</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>6</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>7</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>8</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>9</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>10</td>\n",
       "      <td>1</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   user_id  course_id  rating\n",
       "0        1          1       5\n",
       "1        2          1       5\n",
       "2        3          1       5\n",
       "3        4          1       5\n",
       "4        5          1       5\n",
       "5        6          1       5\n",
       "6        7          1       5\n",
       "7        8          1       5\n",
       "8        9          1       5\n",
       "9       10          1       5"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "unames = ['user_id', 'username']\n",
    "users = pd.read_table('/Users/chengjun/GitHub/cjc2016/data/users_set.dat',\n",
    "                      sep='|', header=None, names=unames)\n",
    "\n",
    "rnames = ['user_id', 'course_id', 'rating']\n",
    "ratings = pd.read_table('/Users/chengjun/GitHub/cjc2016/data/ratings.dat',\n",
    "                        sep='|', header=None, names=rnames)\n",
    "\n",
    "mnames = ['course_id', 'title', 'avg_rating', 'workload', 'university', 'difficulty', 'provider']\n",
    "courses = pd.read_table('/Users/chengjun/GitHub/cjc2016/data/cursos.dat',\n",
    "                       sep='|', header=None, names=mnames)\n",
    "\n",
    "# show how one of them looks\n",
    "ratings.head(10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>user_id</th>\n",
       "      <th>username</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>1</td>\n",
       "      <td>patrickdijusto1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2</td>\n",
       "      <td>natalya_ivanova</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>3</td>\n",
       "      <td>justineittreim</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>4</td>\n",
       "      <td>ronmay</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>5</td>\n",
       "      <td>paulstock</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   user_id         username\n",
       "0        1  patrickdijusto1\n",
       "1        2  natalya_ivanova\n",
       "2        3   justineittreim\n",
       "3        4           ronmay\n",
       "4        5        paulstock"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# show how one of them looks\n",
    "users[:5]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>course_id</th>\n",
       "      <th>title</th>\n",
       "      <th>avg_rating</th>\n",
       "      <th>workload</th>\n",
       "      <th>university</th>\n",
       "      <th>difficulty</th>\n",
       "      <th>provider</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>1</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2</td>\n",
       "      <td>Modern &amp;amp; Contemporary American Poetry</td>\n",
       "      <td>4.9</td>\n",
       "      <td>5-9 hours/week</td>\n",
       "      <td>University of Pennsylvania</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>coursera</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>3</td>\n",
       "      <td>A Beginner&amp;#39;s Guide to Irrational Behavior</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Duke University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>4</td>\n",
       "      <td>Design: Creation of Artifacts in Society</td>\n",
       "      <td>4.9</td>\n",
       "      <td>5-10 hours/week</td>\n",
       "      <td>University of Pennsylvania</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>5</td>\n",
       "      <td>Greek and Roman Mythology</td>\n",
       "      <td>4.9</td>\n",
       "      <td>8-10 hours/week</td>\n",
       "      <td>University of Pennsylvania</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   course_id                                              title avg_rating  \\\n",
       "0          1  An Introduction to Interactive Programming in ...        4.9   \n",
       "1          2          Modern &amp; Contemporary American Poetry        4.9   \n",
       "2          3      A Beginner&#39;s Guide to Irrational Behavior        4.9   \n",
       "3          4           Design: Creation of Artifacts in Society        4.9   \n",
       "4          5                          Greek and Roman Mythology        4.9   \n",
       "\n",
       "          workload                  university   difficulty  provider  \n",
       "0  7-10 hours/week             Rice University       Medium  coursera  \n",
       "1   5-9 hours/week  University of Pennsylvania  Easy/medium  coursera  \n",
       "2  7-10 hours/week             Duke University       Medium  coursera  \n",
       "3  5-10 hours/week  University of Pennsylvania       Medium  coursera  \n",
       "4  8-10 hours/week  University of Pennsylvania       Medium  coursera  "
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "courses[:5]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Using `pd.merge` we get it all into  one big DataFrame."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>user_id</th>\n",
       "      <th>course_id</th>\n",
       "      <th>rating</th>\n",
       "      <th>title</th>\n",
       "      <th>avg_rating</th>\n",
       "      <th>workload</th>\n",
       "      <th>university</th>\n",
       "      <th>difficulty</th>\n",
       "      <th>provider</th>\n",
       "      <th>username</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>patrickdijusto1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>2</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>natalya_ivanova</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>3</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>justineittreim</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>4</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>ronmay</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>paulstock</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>6</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>6</td>\n",
       "      <td>11</td>\n",
       "      <td>4.5</td>\n",
       "      <td>Functional Programming Principles in Scala</td>\n",
       "      <td>4.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Ecole Polytechnique Federale de Lausanne</td>\n",
       "      <td>Medium/hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>6</td>\n",
       "      <td>12</td>\n",
       "      <td>4.0</td>\n",
       "      <td>Gamification</td>\n",
       "      <td>4.8</td>\n",
       "      <td>4-8 hours/week</td>\n",
       "      <td>University of Pennsylvania</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>6</td>\n",
       "      <td>19</td>\n",
       "      <td>5.0</td>\n",
       "      <td>M101P: MongoDB for Developers</td>\n",
       "      <td>4.7</td>\n",
       "      <td>TBA</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>None</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>6</td>\n",
       "      <td>21</td>\n",
       "      <td>5.0</td>\n",
       "      <td>6.002x: Circuits and Electronics</td>\n",
       "      <td>4.7</td>\n",
       "      <td>12 hours/week.</td>\n",
       "      <td>MIT</td>\n",
       "      <td>Medium/hard</td>\n",
       "      <td>edx</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>6</td>\n",
       "      <td>32</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Internet History, Technology, and Security</td>\n",
       "      <td>4.6</td>\n",
       "      <td>3-5 hours/week</td>\n",
       "      <td>University of Michigan</td>\n",
       "      <td>Easy</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>6</td>\n",
       "      <td>33</td>\n",
       "      <td>4.0</td>\n",
       "      <td>Web Development</td>\n",
       "      <td>4.6</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>udacity</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>6</td>\n",
       "      <td>93</td>\n",
       "      <td>5.0</td>\n",
       "      <td>CS-169.1x: Software as a Service</td>\n",
       "      <td>4.2</td>\n",
       "      <td>TBA</td>\n",
       "      <td>UC Berkeley</td>\n",
       "      <td>Medium</td>\n",
       "      <td>edx</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>6</td>\n",
       "      <td>108</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Human-Computer Interaction</td>\n",
       "      <td>4.1</td>\n",
       "      <td>10-12 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>6</td>\n",
       "      <td>134</td>\n",
       "      <td>2.0</td>\n",
       "      <td>Web Intelligence and Big Data</td>\n",
       "      <td>3.9</td>\n",
       "      <td>3-4 hours/week</td>\n",
       "      <td>Indian Institute of Technology Delhi</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>6</td>\n",
       "      <td>141</td>\n",
       "      <td>4.0</td>\n",
       "      <td>Coding the Matrix: Linear Algebra through Comp...</td>\n",
       "      <td>3.8</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Brown University</td>\n",
       "      <td>Medium/hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>6</td>\n",
       "      <td>145</td>\n",
       "      <td>4.0</td>\n",
       "      <td>Game Theory</td>\n",
       "      <td>3.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>6</td>\n",
       "      <td>198</td>\n",
       "      <td>2.0</td>\n",
       "      <td>Software Testing</td>\n",
       "      <td>2.9</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Easy</td>\n",
       "      <td>udacity</td>\n",
       "      <td>boyarsky</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>7</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>barak</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>8</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>alexjeffrey</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>9</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>celsoagustinhernandezdiaz</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>10</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>10</td>\n",
       "      <td>14</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Operations Management</td>\n",
       "      <td>4.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>University of Pennsylvania</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>10</td>\n",
       "      <td>35</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Model Thinking</td>\n",
       "      <td>4.5</td>\n",
       "      <td>4-8 hours/week</td>\n",
       "      <td>University of Michigan</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>10</td>\n",
       "      <td>49</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Fantasy and Science Fiction: The Human Mind, O...</td>\n",
       "      <td>4.5</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>University of Michigan</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>10</td>\n",
       "      <td>87</td>\n",
       "      <td>4.0</td>\n",
       "      <td>Networked Life</td>\n",
       "      <td>4.2</td>\n",
       "      <td>In session</td>\n",
       "      <td>University of Pennsylvania</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>10</td>\n",
       "      <td>142</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Social Network Analysis</td>\n",
       "      <td>3.8</td>\n",
       "      <td>5-7 hours/week (8-10 if completing additional ...</td>\n",
       "      <td>University of Michigan</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>10</td>\n",
       "      <td>188</td>\n",
       "      <td>1.0</td>\n",
       "      <td>Computational Investing, Part I</td>\n",
       "      <td>3.2</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>Georgia Institute of Technology</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>vadimsolomonik</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>11</td>\n",
       "      <td>1</td>\n",
       "      <td>3.5</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>CrunchyCookie</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>12</td>\n",
       "      <td>1</td>\n",
       "      <td>5.0</td>\n",
       "      <td>An Introduction to Interactive Programming in ...</td>\n",
       "      <td>4.9</td>\n",
       "      <td>7-10 hours/week</td>\n",
       "      <td>Rice University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>skywalking</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2743</th>\n",
       "      <td>1988</td>\n",
       "      <td>188</td>\n",
       "      <td>3.0</td>\n",
       "      <td>Computational Investing, Part I</td>\n",
       "      <td>3.2</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>Georgia Institute of Technology</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>alanwilliams</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2744</th>\n",
       "      <td>1989</td>\n",
       "      <td>188</td>\n",
       "      <td>1.0</td>\n",
       "      <td>Computational Investing, Part I</td>\n",
       "      <td>3.2</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>Georgia Institute of Technology</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>Lyon</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2745</th>\n",
       "      <td>1990</td>\n",
       "      <td>188</td>\n",
       "      <td>1.5</td>\n",
       "      <td>Computational Investing, Part I</td>\n",
       "      <td>3.2</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>Georgia Institute of Technology</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>fernandomontenegro</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2746</th>\n",
       "      <td>1991</td>\n",
       "      <td>188</td>\n",
       "      <td>4.5</td>\n",
       "      <td>Computational Investing, Part I</td>\n",
       "      <td>3.2</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>Georgia Institute of Technology</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>lemic</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2747</th>\n",
       "      <td>1992</td>\n",
       "      <td>188</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Computational Investing, Part I</td>\n",
       "      <td>3.2</td>\n",
       "      <td>8-12 hours/week</td>\n",
       "      <td>Georgia Institute of Technology</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>andreamitchell</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2748</th>\n",
       "      <td>1993</td>\n",
       "      <td>189</td>\n",
       "      <td>4.5</td>\n",
       "      <td>CB22x: The Ancient Greek Hero</td>\n",
       "      <td>3.1</td>\n",
       "      <td>TBA</td>\n",
       "      <td>Harvard University</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>edx</td>\n",
       "      <td>megkawento</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2749</th>\n",
       "      <td>1994</td>\n",
       "      <td>189</td>\n",
       "      <td>0.5</td>\n",
       "      <td>CB22x: The Ancient Greek Hero</td>\n",
       "      <td>3.1</td>\n",
       "      <td>TBA</td>\n",
       "      <td>Harvard University</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>edx</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2750</th>\n",
       "      <td>1995</td>\n",
       "      <td>189</td>\n",
       "      <td>2.0</td>\n",
       "      <td>CB22x: The Ancient Greek Hero</td>\n",
       "      <td>3.1</td>\n",
       "      <td>TBA</td>\n",
       "      <td>Harvard University</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>edx</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2751</th>\n",
       "      <td>1996</td>\n",
       "      <td>189</td>\n",
       "      <td>5.0</td>\n",
       "      <td>CB22x: The Ancient Greek Hero</td>\n",
       "      <td>3.1</td>\n",
       "      <td>TBA</td>\n",
       "      <td>Harvard University</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>edx</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2752</th>\n",
       "      <td>1997</td>\n",
       "      <td>190</td>\n",
       "      <td>4.0</td>\n",
       "      <td>Introduction to Systems Biology</td>\n",
       "      <td>3.1</td>\n",
       "      <td>6-8 hours/week</td>\n",
       "      <td>Mount Sinai School of Medicine</td>\n",
       "      <td>Medium/hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2753</th>\n",
       "      <td>1998</td>\n",
       "      <td>192</td>\n",
       "      <td>1.0</td>\n",
       "      <td>Property and Liability: An Introduction to Law...</td>\n",
       "      <td>3.0</td>\n",
       "      <td>2-4 hours/week</td>\n",
       "      <td>Wesleyan University</td>\n",
       "      <td>Easy/medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>echolearning</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2754</th>\n",
       "      <td>1999</td>\n",
       "      <td>193</td>\n",
       "      <td>3.0</td>\n",
       "      <td>Physics</td>\n",
       "      <td>3.0</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>khanacademy</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2755</th>\n",
       "      <td>2000</td>\n",
       "      <td>196</td>\n",
       "      <td>3.0</td>\n",
       "      <td>Poetry: What It Is, and How to Understand It</td>\n",
       "      <td>3.0</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>udemy</td>\n",
       "      <td>marcianuffer</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2756</th>\n",
       "      <td>2001</td>\n",
       "      <td>197</td>\n",
       "      <td>3.0</td>\n",
       "      <td>Principles of Obesity Economics</td>\n",
       "      <td>2.9</td>\n",
       "      <td>3-5 hours/week</td>\n",
       "      <td>Johns Hopkins University</td>\n",
       "      <td>Easy</td>\n",
       "      <td>coursera</td>\n",
       "      <td>irvwiswall</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2757</th>\n",
       "      <td>2002</td>\n",
       "      <td>198</td>\n",
       "      <td>3.5</td>\n",
       "      <td>Software Testing</td>\n",
       "      <td>2.9</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Easy</td>\n",
       "      <td>udacity</td>\n",
       "      <td>ivandutoit</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2758</th>\n",
       "      <td>2003</td>\n",
       "      <td>200</td>\n",
       "      <td>1.0</td>\n",
       "      <td>Introduction to Logic</td>\n",
       "      <td>2.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>llewellynfalco1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2759</th>\n",
       "      <td>2004</td>\n",
       "      <td>200</td>\n",
       "      <td>4.5</td>\n",
       "      <td>Introduction to Logic</td>\n",
       "      <td>2.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2760</th>\n",
       "      <td>2005</td>\n",
       "      <td>200</td>\n",
       "      <td>1.5</td>\n",
       "      <td>Introduction to Logic</td>\n",
       "      <td>2.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>caleesarya</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2761</th>\n",
       "      <td>2006</td>\n",
       "      <td>200</td>\n",
       "      <td>1.0</td>\n",
       "      <td>Introduction to Logic</td>\n",
       "      <td>2.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>nathanhall</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2762</th>\n",
       "      <td>2007</td>\n",
       "      <td>200</td>\n",
       "      <td>5.0</td>\n",
       "      <td>Introduction to Logic</td>\n",
       "      <td>2.8</td>\n",
       "      <td>5-7 hours/week</td>\n",
       "      <td>Stanford University</td>\n",
       "      <td>Medium</td>\n",
       "      <td>coursera</td>\n",
       "      <td>valeria</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2763</th>\n",
       "      <td>2008</td>\n",
       "      <td>205</td>\n",
       "      <td>2.0</td>\n",
       "      <td>Preparation for Introductory Biology: DNA to O...</td>\n",
       "      <td>2.4</td>\n",
       "      <td>8-10 hours/week</td>\n",
       "      <td>UC Irvine</td>\n",
       "      <td>Hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>stuartwilloughby</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2764</th>\n",
       "      <td>2009</td>\n",
       "      <td>207</td>\n",
       "      <td>1.5</td>\n",
       "      <td>Computer Architecture</td>\n",
       "      <td>2.2</td>\n",
       "      <td>5-8 hours/week</td>\n",
       "      <td>Princeton University</td>\n",
       "      <td>Hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>jonsnow</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2765</th>\n",
       "      <td>2010</td>\n",
       "      <td>212</td>\n",
       "      <td>0.5</td>\n",
       "      <td>HTML5 Game Development</td>\n",
       "      <td>1.8</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>udacity</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2766</th>\n",
       "      <td>2011</td>\n",
       "      <td>212</td>\n",
       "      <td>3.0</td>\n",
       "      <td>HTML5 Game Development</td>\n",
       "      <td>1.8</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>udacity</td>\n",
       "      <td>florianschaetz</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2767</th>\n",
       "      <td>2012</td>\n",
       "      <td>212</td>\n",
       "      <td>1.0</td>\n",
       "      <td>HTML5 Game Development</td>\n",
       "      <td>1.8</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>udacity</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2768</th>\n",
       "      <td>2013</td>\n",
       "      <td>212</td>\n",
       "      <td>1.0</td>\n",
       "      <td>HTML5 Game Development</td>\n",
       "      <td>1.8</td>\n",
       "      <td>Self-paced</td>\n",
       "      <td>NaN</td>\n",
       "      <td>Medium</td>\n",
       "      <td>udacity</td>\n",
       "      <td>anonymous</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2769</th>\n",
       "      <td>2014</td>\n",
       "      <td>213</td>\n",
       "      <td>0.5</td>\n",
       "      <td>A New History for a New China, 1700-2000: New ...</td>\n",
       "      <td>1.4</td>\n",
       "      <td>3-4 hours/week</td>\n",
       "      <td>The Hong Kong University of Science and Techno...</td>\n",
       "      <td>Medium/hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>chihchengyuan1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2770</th>\n",
       "      <td>2015</td>\n",
       "      <td>213</td>\n",
       "      <td>0.5</td>\n",
       "      <td>A New History for a New China, 1700-2000: New ...</td>\n",
       "      <td>1.4</td>\n",
       "      <td>3-4 hours/week</td>\n",
       "      <td>The Hong Kong University of Science and Techno...</td>\n",
       "      <td>Medium/hard</td>\n",
       "      <td>coursera</td>\n",
       "      <td>kj</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2771</th>\n",
       "      <td>2016</td>\n",
       "      <td>214</td>\n",
       "      <td>1.0</td>\n",
       "      <td>Sports and Society</td>\n",
       "      <td>1.3</td>\n",
       "      <td>3-5 hours/week</td>\n",
       "      <td>Duke University</td>\n",
       "      <td>Easy</td>\n",
       "      <td>coursera</td>\n",
       "      <td>debbie</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2772</th>\n",
       "      <td>2017</td>\n",
       "      <td>214</td>\n",
       "      <td>0.5</td>\n",
       "      <td>Sports and Society</td>\n",
       "      <td>1.3</td>\n",
       "      <td>3-5 hours/week</td>\n",
       "      <td>Duke University</td>\n",
       "      <td>Easy</td>\n",
       "      <td>coursera</td>\n",
       "      <td>kuba</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>2773 rows × 10 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "      user_id  course_id  rating  \\\n",
       "0           1          1     5.0   \n",
       "1           2          1     5.0   \n",
       "2           3          1     5.0   \n",
       "3           4          1     5.0   \n",
       "4           5          1     5.0   \n",
       "5           6          1     5.0   \n",
       "6           6         11     4.5   \n",
       "7           6         12     4.0   \n",
       "8           6         19     5.0   \n",
       "9           6         21     5.0   \n",
       "10          6         32     5.0   \n",
       "11          6         33     4.0   \n",
       "12          6         93     5.0   \n",
       "13          6        108     5.0   \n",
       "14          6        134     2.0   \n",
       "15          6        141     4.0   \n",
       "16          6        145     4.0   \n",
       "17          6        198     2.0   \n",
       "18          7          1     5.0   \n",
       "19          8          1     5.0   \n",
       "20          9          1     5.0   \n",
       "21         10          1     5.0   \n",
       "22         10         14     5.0   \n",
       "23         10         35     5.0   \n",
       "24         10         49     5.0   \n",
       "25         10         87     4.0   \n",
       "26         10        142     5.0   \n",
       "27         10        188     1.0   \n",
       "28         11          1     3.5   \n",
       "29         12          1     5.0   \n",
       "...       ...        ...     ...   \n",
       "2743     1988        188     3.0   \n",
       "2744     1989        188     1.0   \n",
       "2745     1990        188     1.5   \n",
       "2746     1991        188     4.5   \n",
       "2747     1992        188     5.0   \n",
       "2748     1993        189     4.5   \n",
       "2749     1994        189     0.5   \n",
       "2750     1995        189     2.0   \n",
       "2751     1996        189     5.0   \n",
       "2752     1997        190     4.0   \n",
       "2753     1998        192     1.0   \n",
       "2754     1999        193     3.0   \n",
       "2755     2000        196     3.0   \n",
       "2756     2001        197     3.0   \n",
       "2757     2002        198     3.5   \n",
       "2758     2003        200     1.0   \n",
       "2759     2004        200     4.5   \n",
       "2760     2005        200     1.5   \n",
       "2761     2006        200     1.0   \n",
       "2762     2007        200     5.0   \n",
       "2763     2008        205     2.0   \n",
       "2764     2009        207     1.5   \n",
       "2765     2010        212     0.5   \n",
       "2766     2011        212     3.0   \n",
       "2767     2012        212     1.0   \n",
       "2768     2013        212     1.0   \n",
       "2769     2014        213     0.5   \n",
       "2770     2015        213     0.5   \n",
       "2771     2016        214     1.0   \n",
       "2772     2017        214     0.5   \n",
       "\n",
       "                                                  title avg_rating  \\\n",
       "0     An Introduction to Interactive Programming in ...        4.9   \n",
       "1     An Introduction to Interactive Programming in ...        4.9   \n",
       "2     An Introduction to Interactive Programming in ...        4.9   \n",
       "3     An Introduction to Interactive Programming in ...        4.9   \n",
       "4     An Introduction to Interactive Programming in ...        4.9   \n",
       "5     An Introduction to Interactive Programming in ...        4.9   \n",
       "6            Functional Programming Principles in Scala        4.8   \n",
       "7                                          Gamification        4.8   \n",
       "8                         M101P: MongoDB for Developers        4.7   \n",
       "9                      6.002x: Circuits and Electronics        4.7   \n",
       "10           Internet History, Technology, and Security        4.6   \n",
       "11                                      Web Development        4.6   \n",
       "12                     CS-169.1x: Software as a Service        4.2   \n",
       "13                           Human-Computer Interaction        4.1   \n",
       "14                        Web Intelligence and Big Data        3.9   \n",
       "15    Coding the Matrix: Linear Algebra through Comp...        3.8   \n",
       "16                                          Game Theory        3.8   \n",
       "17                                     Software Testing        2.9   \n",
       "18    An Introduction to Interactive Programming in ...        4.9   \n",
       "19    An Introduction to Interactive Programming in ...        4.9   \n",
       "20    An Introduction to Interactive Programming in ...        4.9   \n",
       "21    An Introduction to Interactive Programming in ...        4.9   \n",
       "22             An Introduction to Operations Management        4.8   \n",
       "23                                       Model Thinking        4.5   \n",
       "24    Fantasy and Science Fiction: The Human Mind, O...        4.5   \n",
       "25                                       Networked Life        4.2   \n",
       "26                              Social Network Analysis        3.8   \n",
       "27                      Computational Investing, Part I        3.2   \n",
       "28    An Introduction to Interactive Programming in ...        4.9   \n",
       "29    An Introduction to Interactive Programming in ...        4.9   \n",
       "...                                                 ...        ...   \n",
       "2743                    Computational Investing, Part I        3.2   \n",
       "2744                    Computational Investing, Part I        3.2   \n",
       "2745                    Computational Investing, Part I        3.2   \n",
       "2746                    Computational Investing, Part I        3.2   \n",
       "2747                    Computational Investing, Part I        3.2   \n",
       "2748                      CB22x: The Ancient Greek Hero        3.1   \n",
       "2749                      CB22x: The Ancient Greek Hero        3.1   \n",
       "2750                      CB22x: The Ancient Greek Hero        3.1   \n",
       "2751                      CB22x: The Ancient Greek Hero        3.1   \n",
       "2752                    Introduction to Systems Biology        3.1   \n",
       "2753  Property and Liability: An Introduction to Law...        3.0   \n",
       "2754                                            Physics        3.0   \n",
       "2755       Poetry: What It Is, and How to Understand It        3.0   \n",
       "2756                    Principles of Obesity Economics        2.9   \n",
       "2757                                   Software Testing        2.9   \n",
       "2758                              Introduction to Logic        2.8   \n",
       "2759                              Introduction to Logic        2.8   \n",
       "2760                              Introduction to Logic        2.8   \n",
       "2761                              Introduction to Logic        2.8   \n",
       "2762                              Introduction to Logic        2.8   \n",
       "2763  Preparation for Introductory Biology: DNA to O...        2.4   \n",
       "2764                              Computer Architecture        2.2   \n",
       "2765                             HTML5 Game Development        1.8   \n",
       "2766                             HTML5 Game Development        1.8   \n",
       "2767                             HTML5 Game Development        1.8   \n",
       "2768                             HTML5 Game Development        1.8   \n",
       "2769  A New History for a New China, 1700-2000: New ...        1.4   \n",
       "2770  A New History for a New China, 1700-2000: New ...        1.4   \n",
       "2771                                 Sports and Society        1.3   \n",
       "2772                                 Sports and Society        1.3   \n",
       "\n",
       "                                               workload  \\\n",
       "0                                       7-10 hours/week   \n",
       "1                                       7-10 hours/week   \n",
       "2                                       7-10 hours/week   \n",
       "3                                       7-10 hours/week   \n",
       "4                                       7-10 hours/week   \n",
       "5                                       7-10 hours/week   \n",
       "6                                        5-7 hours/week   \n",
       "7                                        4-8 hours/week   \n",
       "8                                                  TBA    \n",
       "9                                        12 hours/week.   \n",
       "10                                       3-5 hours/week   \n",
       "11                                          Self-paced    \n",
       "12                                                 TBA    \n",
       "13                                     10-12 hours/week   \n",
       "14                                       3-4 hours/week   \n",
       "15                                      7-10 hours/week   \n",
       "16                                       5-7 hours/week   \n",
       "17                                          Self-paced    \n",
       "18                                      7-10 hours/week   \n",
       "19                                      7-10 hours/week   \n",
       "20                                      7-10 hours/week   \n",
       "21                                      7-10 hours/week   \n",
       "22                                       5-7 hours/week   \n",
       "23                                       4-8 hours/week   \n",
       "24                                      8-12 hours/week   \n",
       "25                                           In session   \n",
       "26    5-7 hours/week (8-10 if completing additional ...   \n",
       "27                                      8-12 hours/week   \n",
       "28                                      7-10 hours/week   \n",
       "29                                      7-10 hours/week   \n",
       "...                                                 ...   \n",
       "2743                                    8-12 hours/week   \n",
       "2744                                    8-12 hours/week   \n",
       "2745                                    8-12 hours/week   \n",
       "2746                                    8-12 hours/week   \n",
       "2747                                    8-12 hours/week   \n",
       "2748                                               TBA    \n",
       "2749                                               TBA    \n",
       "2750                                               TBA    \n",
       "2751                                               TBA    \n",
       "2752                                     6-8 hours/week   \n",
       "2753                                     2-4 hours/week   \n",
       "2754                                        Self-paced    \n",
       "2755                                        Self-paced    \n",
       "2756                                     3-5 hours/week   \n",
       "2757                                        Self-paced    \n",
       "2758                                     5-7 hours/week   \n",
       "2759                                     5-7 hours/week   \n",
       "2760                                     5-7 hours/week   \n",
       "2761                                     5-7 hours/week   \n",
       "2762                                     5-7 hours/week   \n",
       "2763                                    8-10 hours/week   \n",
       "2764                                     5-8 hours/week   \n",
       "2765                                        Self-paced    \n",
       "2766                                        Self-paced    \n",
       "2767                                        Self-paced    \n",
       "2768                                        Self-paced    \n",
       "2769                                     3-4 hours/week   \n",
       "2770                                     3-4 hours/week   \n",
       "2771                                     3-5 hours/week   \n",
       "2772                                     3-5 hours/week   \n",
       "\n",
       "                                             university   difficulty  \\\n",
       "0                                       Rice University       Medium   \n",
       "1                                       Rice University       Medium   \n",
       "2                                       Rice University       Medium   \n",
       "3                                       Rice University       Medium   \n",
       "4                                       Rice University       Medium   \n",
       "5                                       Rice University       Medium   \n",
       "6              Ecole Polytechnique Federale de Lausanne  Medium/hard   \n",
       "7                            University of Pennsylvania  Easy/medium   \n",
       "8                                                   NaN       Medium   \n",
       "9                                                   MIT  Medium/hard   \n",
       "10                               University of Michigan         Easy   \n",
       "11                                                  NaN  Easy/medium   \n",
       "12                                          UC Berkeley       Medium   \n",
       "13                                  Stanford University  Easy/medium   \n",
       "14                 Indian Institute of Technology Delhi       Medium   \n",
       "15                                     Brown University  Medium/hard   \n",
       "16                                  Stanford University       Medium   \n",
       "17                                                  NaN         Easy   \n",
       "18                                      Rice University       Medium   \n",
       "19                                      Rice University       Medium   \n",
       "20                                      Rice University       Medium   \n",
       "21                                      Rice University       Medium   \n",
       "22                           University of Pennsylvania       Medium   \n",
       "23                               University of Michigan  Easy/medium   \n",
       "24                               University of Michigan       Medium   \n",
       "25                           University of Pennsylvania  Easy/medium   \n",
       "26                               University of Michigan       Medium   \n",
       "27                      Georgia Institute of Technology       Medium   \n",
       "28                                      Rice University       Medium   \n",
       "29                                      Rice University       Medium   \n",
       "...                                                 ...          ...   \n",
       "2743                    Georgia Institute of Technology       Medium   \n",
       "2744                    Georgia Institute of Technology       Medium   \n",
       "2745                    Georgia Institute of Technology       Medium   \n",
       "2746                    Georgia Institute of Technology       Medium   \n",
       "2747                    Georgia Institute of Technology       Medium   \n",
       "2748                                 Harvard University  Easy/medium   \n",
       "2749                                 Harvard University  Easy/medium   \n",
       "2750                                 Harvard University  Easy/medium   \n",
       "2751                                 Harvard University  Easy/medium   \n",
       "2752                     Mount Sinai School of Medicine  Medium/hard   \n",
       "2753                                Wesleyan University  Easy/medium   \n",
       "2754                                                NaN       Medium   \n",
       "2755                                                NaN       Medium   \n",
       "2756                           Johns Hopkins University         Easy   \n",
       "2757                                                NaN         Easy   \n",
       "2758                                Stanford University       Medium   \n",
       "2759                                Stanford University       Medium   \n",
       "2760                                Stanford University       Medium   \n",
       "2761                                Stanford University       Medium   \n",
       "2762                                Stanford University       Medium   \n",
       "2763                                          UC Irvine         Hard   \n",
       "2764                               Princeton University         Hard   \n",
       "2765                                                NaN       Medium   \n",
       "2766                                                NaN       Medium   \n",
       "2767                                                NaN       Medium   \n",
       "2768                                                NaN       Medium   \n",
       "2769  The Hong Kong University of Science and Techno...  Medium/hard   \n",
       "2770  The Hong Kong University of Science and Techno...  Medium/hard   \n",
       "2771                                    Duke University         Easy   \n",
       "2772                                    Duke University         Easy   \n",
       "\n",
       "         provider                   username  \n",
       "0        coursera            patrickdijusto1  \n",
       "1        coursera            natalya_ivanova  \n",
       "2        coursera             justineittreim  \n",
       "3        coursera                     ronmay  \n",
       "4        coursera                  paulstock  \n",
       "5        coursera                   boyarsky  \n",
       "6        coursera                   boyarsky  \n",
       "7        coursera                   boyarsky  \n",
       "8            None                   boyarsky  \n",
       "9             edx                   boyarsky  \n",
       "10       coursera                   boyarsky  \n",
       "11        udacity                   boyarsky  \n",
       "12            edx                   boyarsky  \n",
       "13       coursera                   boyarsky  \n",
       "14       coursera                   boyarsky  \n",
       "15       coursera                   boyarsky  \n",
       "16       coursera                   boyarsky  \n",
       "17        udacity                   boyarsky  \n",
       "18       coursera                      barak  \n",
       "19       coursera                alexjeffrey  \n",
       "20       coursera  celsoagustinhernandezdiaz  \n",
       "21       coursera             vadimsolomonik  \n",
       "22       coursera             vadimsolomonik  \n",
       "23       coursera             vadimsolomonik  \n",
       "24       coursera             vadimsolomonik  \n",
       "25       coursera             vadimsolomonik  \n",
       "26       coursera             vadimsolomonik  \n",
       "27       coursera             vadimsolomonik  \n",
       "28       coursera              CrunchyCookie  \n",
       "29       coursera                 skywalking  \n",
       "...           ...                        ...  \n",
       "2743     coursera               alanwilliams  \n",
       "2744     coursera                       Lyon  \n",
       "2745     coursera         fernandomontenegro  \n",
       "2746     coursera                      lemic  \n",
       "2747     coursera             andreamitchell  \n",
       "2748          edx                 megkawento  \n",
       "2749          edx                  anonymous  \n",
       "2750          edx                  anonymous  \n",
       "2751          edx                  anonymous  \n",
       "2752     coursera                  anonymous  \n",
       "2753     coursera               echolearning  \n",
       "2754  khanacademy                  anonymous  \n",
       "2755        udemy               marcianuffer  \n",
       "2756     coursera                 irvwiswall  \n",
       "2757      udacity                 ivandutoit  \n",
       "2758     coursera            llewellynfalco1  \n",
       "2759     coursera                  anonymous  \n",
       "2760     coursera                 caleesarya  \n",
       "2761     coursera                 nathanhall  \n",
       "2762     coursera                    valeria  \n",
       "2763     coursera           stuartwilloughby  \n",
       "2764     coursera                    jonsnow  \n",
       "2765      udacity                  anonymous  \n",
       "2766      udacity             florianschaetz  \n",
       "2767      udacity                  anonymous  \n",
       "2768      udacity                  anonymous  \n",
       "2769     coursera             chihchengyuan1  \n",
       "2770     coursera                         kj  \n",
       "2771     coursera                     debbie  \n",
       "2772     coursera                       kuba  \n",
       "\n",
       "[2773 rows x 10 columns]"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "coursetalk = pd.merge(pd.merge(ratings, courses), users)\n",
    "coursetalk"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "user_id                                                       1\n",
       "course_id                                                     1\n",
       "rating                                                        5\n",
       "title         An Introduction to Interactive Programming in ...\n",
       "avg_rating                                                  4.9\n",
       "workload                                        7-10 hours/week\n",
       "university                                      Rice University\n",
       "difficulty                                               Medium\n",
       "provider                                               coursera\n",
       "username                                        patrickdijusto1\n",
       "Name: 0, dtype: object"
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "coursetalk.ix[0]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Collaborative filtering: generalizations of the aggregation function\n",
    "\n",
    "#### Non-personalized recommendations\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Groupby\n",
    "\n",
    "The idea of groupby is that of *split-apply-combine*:\n",
    "\n",
    "- split data in an object according to a given key;\n",
    "- apply a function to each subset;\n",
    "- combine results into a new object."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    " To get mean course ratings grouped by the provider, we can use the pivot_table method:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['__call__',\n",
       " '__class__',\n",
       " '__closure__',\n",
       " '__code__',\n",
       " '__defaults__',\n",
       " '__delattr__',\n",
       " '__dict__',\n",
       " '__doc__',\n",
       " '__format__',\n",
       " '__get__',\n",
       " '__getattribute__',\n",
       " '__globals__',\n",
       " '__hash__',\n",
       " '__init__',\n",
       " '__module__',\n",
       " '__name__',\n",
       " '__new__',\n",
       " '__reduce__',\n",
       " '__reduce_ex__',\n",
       " '__repr__',\n",
       " '__setattr__',\n",
       " '__sizeof__',\n",
       " '__str__',\n",
       " '__subclasshook__',\n",
       " 'func_closure',\n",
       " 'func_code',\n",
       " 'func_defaults',\n",
       " 'func_dict',\n",
       " 'func_doc',\n",
       " 'func_globals',\n",
       " 'func_name']"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "dir(pivot_table)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "provider\n",
       "None            4.562500\n",
       "coursera        4.527835\n",
       "edx             4.491620\n",
       "codecademy      4.450000\n",
       "udacity         4.241071\n",
       "udemy           4.200000\n",
       "open2study      4.083333\n",
       "khanacademy     4.000000\n",
       "novoed          3.281250\n",
       "mruniversity    3.250000\n",
       "Name: rating, dtype: float64"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "from pandas import pivot_table\n",
    "mean_ratings = pivot_table(coursetalk, values = 'rating', columns='provider', aggfunc='mean')\n",
    "mean_ratings.order(ascending=False)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now let's filter down to courses that received at least 20 ratings (a completely arbitrary number);\n",
    "To do this, I group the data by course_id and use size() to get a Series of group sizes for each title:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "title\n",
       "14.73x: The Challenges of Global Poverty                     2\n",
       "2.01x: Elements of Structures                                2\n",
       "3.091x: Introduction to Solid State Chemistry                3\n",
       "6.002x: Circuits and Electronics                            10\n",
       "6.00x: Introduction to Computer Science and Programming     21\n",
       "7.00x: Introduction to Biology - The Secret of Life          3\n",
       "8.02x: Electricity and Magnetism                             3\n",
       "8.MReVx: Mechanics ReView                                    1\n",
       "A Beginner&#39;s Guide to Irrational Behavior              147\n",
       "A Crash Course on Creativity                                 5\n",
       "dtype: int64"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ratings_by_title = coursetalk.groupby('title').size()\n",
    "ratings_by_title[:10]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Index([u'6.00x: Introduction to Computer Science and Programming',\n",
       "       u'A Beginner&#39;s Guide to Irrational Behavior',\n",
       "       u'An Introduction to Interactive Programming in Python',\n",
       "       u'An Introduction to Operations Management',\n",
       "       u'CS-191x: Quantum Mechanics and Quantum Computation',\n",
       "       u'CS188.1x Artificial Intelligence', u'Calculus: Single Variable',\n",
       "       u'Computing for Data Analysis',\n",
       "       u'Critical Thinking in Global Challenges', u'Cryptography I'],\n",
       "      dtype='object', name=u'title')"
      ]
     },
     "execution_count": 17,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "active_titles = ratings_by_title.index[ratings_by_title >= 20]\n",
    "active_titles[:10]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The index of titles receiving at least 20 ratings can then be used to select rows from mean_ratings above:\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "title\n",
       "14.73x: The Challenges of Global Poverty                                      4.250000\n",
       "2.01x: Elements of Structures                                                 4.750000\n",
       "3.091x: Introduction to Solid State Chemistry                                 4.166667\n",
       "6.002x: Circuits and Electronics                                              4.800000\n",
       "6.00x: Introduction to Computer Science and Programming                       4.166667\n",
       "7.00x: Introduction to Biology - The Secret of Life                           4.666667\n",
       "8.02x: Electricity and Magnetism                                              4.333333\n",
       "8.MReVx: Mechanics ReView                                                     5.000000\n",
       "A Beginner&#39;s Guide to Irrational Behavior                                 4.874150\n",
       "A Crash Course on Creativity                                                  3.500000\n",
       "A History of the World since 1300                                             4.318182\n",
       "A Look at Nuclear Science and Technology                                      3.000000\n",
       "A New History for a New China, 1700-2000: New Data and New Methods, Part 1    0.500000\n",
       "AIDS                                                                          5.000000\n",
       "Aboriginal Worldviews and Education                                           4.333333\n",
       "Algorithms                                                                    4.250000\n",
       "Algorithms, Part I                                                            4.555556\n",
       "Algorithms, Part II                                                           4.500000\n",
       "Algorithms: Design and Analysis, Part 1                                       4.777778\n",
       "Algorithms: Design and Analysis, Part 2                                       4.500000\n",
       "An Introduction to Interactive Programming in Python                          4.915652\n",
       "An Introduction to Operations Management                                      4.785714\n",
       "An Introduction to the U.S. Food System: Perspectives from Public Health      5.000000\n",
       "Animal Behaviour                                                              4.500000\n",
       "Applied Cryptography                                                          4.666667\n",
       "Archaeology&#39;s Dirty Little Secrets                                        4.928571\n",
       "Artificial Intelligence Planning                                              3.250000\n",
       "Artificial Intelligence for Robotics                                          4.333333\n",
       "Astrobiology and the Search for Extraterrestrial Life                         3.928571\n",
       "Automata                                                                      4.000000\n",
       "                                                                                ...   \n",
       "Sports and Society                                                            0.666667\n",
       "Stat2.1X: Introduction to Statistics: Descriptive Statistics                  4.642857\n",
       "Stat2.2x: Introduction to Statistics: Probability                             5.000000\n",
       "Stat2.3x: Introduction to Statistics: Inference                               4.500000\n",
       "Statistics One                                                                3.909091\n",
       "Synapses, Neurons and Brains                                                  4.600000\n",
       "Teaching Adult Learners (WPTrain)                                             2.500000\n",
       "Technology Entrepreneurship Part 1                                            2.900000\n",
       "Technology Entrepreneurship Part 2                                            0.500000\n",
       "The Ancient Greeks                                                            4.550000\n",
       "The Eurozone Crisis                                                           3.250000\n",
       "The Fiction of Relationship                                                   5.000000\n",
       "The Hardware/Software Interface                                               3.857143\n",
       "The Language of Hollywood: Storytelling, Sound, and Color                     4.800000\n",
       "The Massey Method: Learn Spanish from a Former NSA Agent                      4.000000\n",
       "The Modern World: Global History since 1760                                   4.775862\n",
       "The Modern and the Postmodern                                                 4.777778\n",
       "The Science of Gastronomy                                                     4.000000\n",
       "The Social Context of Mental Health and Illness                               4.333333\n",
       "Think Again: How to Reason and Argue                                          3.815789\n",
       "Useful Genetics Part 1                                                        4.500000\n",
       "VLSI CAD:  Logic to Layout                                                    4.500000\n",
       "Vaccine Trials: Methods and Best Practices                                    5.000000\n",
       "Vaccines                                                                      3.750000\n",
       "Web Development                                                               4.625000\n",
       "Web Intelligence and Big Data                                                 3.802326\n",
       "Women and the Civil Rights Movement                                           5.000000\n",
       "Writing for the Web (WriteWeb)                                                5.000000\n",
       "Writing in the Sciences                                                       4.000000\n",
       "jQuery                                                                        4.250000\n",
       "Name: rating, dtype: float64"
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mean_ratings = coursetalk.pivot_table('rating', columns='title', aggfunc='mean')\n",
    "mean_ratings"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "By computing the mean rating for each course, we will order with the highest rating listed first.\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "title\n",
       "An Introduction to Interactive Programming in Python             4.915652\n",
       "Modern &amp; Contemporary American Poetry                        4.901515\n",
       "Design: Creation of Artifacts in Society                         4.879581\n",
       "A Beginner&#39;s Guide to Irrational Behavior                    4.874150\n",
       "Greek and Roman Mythology                                        4.864198\n",
       "Calculus: Single Variable                                        4.854167\n",
       "CS188.1x Artificial Intelligence                                 4.833333\n",
       "Machine Learning                                                 4.830000\n",
       "Functional Programming Principles in Scala                       4.822581\n",
       "Gamification                                                     4.796296\n",
       "An Introduction to Operations Management                         4.785714\n",
       "The Modern World: Global History since 1760                      4.775862\n",
       "Programming Languages                                            4.770833\n",
       "CS-191x: Quantum Mechanics and Quantum Computation               4.727273\n",
       "Cryptography I                                                   4.700000\n",
       "Discrete Optimization                                            4.695652\n",
       "Introduction to Computer Science                                 4.687500\n",
       "Learn to Program: Crafting Quality Code                          4.585714\n",
       "Model Thinking                                                   4.578125\n",
       "Internet History, Technology, and Security                       4.541667\n",
       "Fantasy and Science Fiction: The Human Mind, Our Modern World    4.522727\n",
       "Learn to Program: The Fundamentals                               4.303571\n",
       "6.00x: Introduction to Computer Science and Programming          4.166667\n",
       "Critical Thinking in Global Challenges                           3.961538\n",
       "Web Intelligence and Big Data                                    3.802326\n",
       "Computing for Data Analysis                                      3.187500\n",
       "Introduction to Finance                                          3.086957\n",
       "Introduction to Data Science                                     3.060000\n",
       "Name: rating, dtype: float64"
      ]
     },
     "execution_count": 19,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mean_ratings.ix[active_titles].order(ascending=False)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "To see the top courses among Coursera students, we can sort by the 'Coursera' column in descending order:\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th>provider</th>\n",
       "      <th>None</th>\n",
       "      <th>codecademy</th>\n",
       "      <th>coursera</th>\n",
       "      <th>edx</th>\n",
       "      <th>khanacademy</th>\n",
       "      <th>mruniversity</th>\n",
       "      <th>novoed</th>\n",
       "      <th>open2study</th>\n",
       "      <th>udacity</th>\n",
       "      <th>udemy</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>title</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.250000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.750000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.166667</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.800000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.166667</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.666667</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.333333</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>5.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>4.87415</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>3.5</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "provider                                            None  codecademy  \\\n",
       "title                                                                  \n",
       "14.73x: The Challenges of Global Poverty             NaN         NaN   \n",
       "2.01x: Elements of Structures                        NaN         NaN   \n",
       "3.091x: Introduction to Solid State Chemistry        NaN         NaN   \n",
       "6.002x: Circuits and Electronics                     NaN         NaN   \n",
       "6.00x: Introduction to Computer Science and Pro...   NaN         NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ...   NaN         NaN   \n",
       "8.02x: Electricity and Magnetism                     NaN         NaN   \n",
       "8.MReVx: Mechanics ReView                            NaN         NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior        NaN         NaN   \n",
       "A Crash Course on Creativity                         NaN         NaN   \n",
       "\n",
       "provider                                            coursera       edx  \\\n",
       "title                                                                    \n",
       "14.73x: The Challenges of Global Poverty                 NaN  4.250000   \n",
       "2.01x: Elements of Structures                            NaN  4.750000   \n",
       "3.091x: Introduction to Solid State Chemistry            NaN  4.166667   \n",
       "6.002x: Circuits and Electronics                         NaN  4.800000   \n",
       "6.00x: Introduction to Computer Science and Pro...       NaN  4.166667   \n",
       "7.00x: Introduction to Biology - The Secret of ...       NaN  4.666667   \n",
       "8.02x: Electricity and Magnetism                         NaN  4.333333   \n",
       "8.MReVx: Mechanics ReView                                NaN  5.000000   \n",
       "A Beginner&#39;s Guide to Irrational Behavior        4.87415       NaN   \n",
       "A Crash Course on Creativity                             NaN       NaN   \n",
       "\n",
       "provider                                            khanacademy  mruniversity  \\\n",
       "title                                                                           \n",
       "14.73x: The Challenges of Global Poverty                    NaN           NaN   \n",
       "2.01x: Elements of Structures                               NaN           NaN   \n",
       "3.091x: Introduction to Solid State Chemistry               NaN           NaN   \n",
       "6.002x: Circuits and Electronics                            NaN           NaN   \n",
       "6.00x: Introduction to Computer Science and Pro...          NaN           NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ...          NaN           NaN   \n",
       "8.02x: Electricity and Magnetism                            NaN           NaN   \n",
       "8.MReVx: Mechanics ReView                                   NaN           NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior               NaN           NaN   \n",
       "A Crash Course on Creativity                                NaN           NaN   \n",
       "\n",
       "provider                                            novoed  open2study  \\\n",
       "title                                                                    \n",
       "14.73x: The Challenges of Global Poverty               NaN         NaN   \n",
       "2.01x: Elements of Structures                          NaN         NaN   \n",
       "3.091x: Introduction to Solid State Chemistry          NaN         NaN   \n",
       "6.002x: Circuits and Electronics                       NaN         NaN   \n",
       "6.00x: Introduction to Computer Science and Pro...     NaN         NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ...     NaN         NaN   \n",
       "8.02x: Electricity and Magnetism                       NaN         NaN   \n",
       "8.MReVx: Mechanics ReView                              NaN         NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior          NaN         NaN   \n",
       "A Crash Course on Creativity                           3.5         NaN   \n",
       "\n",
       "provider                                            udacity  udemy  \n",
       "title                                                               \n",
       "14.73x: The Challenges of Global Poverty                NaN    NaN  \n",
       "2.01x: Elements of Structures                           NaN    NaN  \n",
       "3.091x: Introduction to Solid State Chemistry           NaN    NaN  \n",
       "6.002x: Circuits and Electronics                        NaN    NaN  \n",
       "6.00x: Introduction to Computer Science and Pro...      NaN    NaN  \n",
       "7.00x: Introduction to Biology - The Secret of ...      NaN    NaN  \n",
       "8.02x: Electricity and Magnetism                        NaN    NaN  \n",
       "8.MReVx: Mechanics ReView                               NaN    NaN  \n",
       "A Beginner&#39;s Guide to Irrational Behavior           NaN    NaN  \n",
       "A Crash Course on Creativity                            NaN    NaN  "
      ]
     },
     "execution_count": 20,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mean_ratings = coursetalk.pivot_table('rating', index='title',columns='provider', aggfunc='mean')\n",
    "mean_ratings[:10]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "title\n",
       "An Introduction to Interactive Programming in Python    4.915652\n",
       "Modern &amp; Contemporary American Poetry               4.901515\n",
       "Design: Creation of Artifacts in Society                4.879581\n",
       "A Beginner&#39;s Guide to Irrational Behavior           4.874150\n",
       "Greek and Roman Mythology                               4.864198\n",
       "Calculus: Single Variable                               4.854167\n",
       "Programming Languages                                   4.850000\n",
       "Machine Learning                                        4.830000\n",
       "Functional Programming Principles in Scala              4.822581\n",
       "Gamification                                            4.796296\n",
       "Name: coursera, dtype: float64"
      ]
     },
     "execution_count": 21,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mean_ratings['coursera'][active_titles].order(ascending=False)[:10]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "\n",
    "Now, let's go further!  How about rank the courses with the highest percentage of ratings that are 4 or higher ?  % of ratings 4+\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Let's start with a simple pivoting example that does not involve any aggregation. We can extract a ratings matrix as follows:\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th>title</th>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <th>A History of the World since 1300</th>\n",
       "      <th>A Look at Nuclear Science and Technology</th>\n",
       "      <th>A New History for a New China, 1700-2000: New Data and New Methods, Part 1</th>\n",
       "      <th>AIDS</th>\n",
       "      <th>Aboriginal Worldviews and Education</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>user_id</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>5</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "title    14.73x: The Challenges of Global Poverty  \\\n",
       "user_id                                             \n",
       "1                                             NaN   \n",
       "2                                             NaN   \n",
       "3                                             NaN   \n",
       "4                                             NaN   \n",
       "5                                             NaN   \n",
       "6                                             NaN   \n",
       "7                                             NaN   \n",
       "8                                             NaN   \n",
       "9                                             NaN   \n",
       "10                                            NaN   \n",
       "11                                            NaN   \n",
       "12                                            NaN   \n",
       "13                                            NaN   \n",
       "14                                            NaN   \n",
       "15                                            NaN   \n",
       "\n",
       "title    2.01x: Elements of Structures  \\\n",
       "user_id                                  \n",
       "1                                  NaN   \n",
       "2                                  NaN   \n",
       "3                                  NaN   \n",
       "4                                  NaN   \n",
       "5                                  NaN   \n",
       "6                                  NaN   \n",
       "7                                  NaN   \n",
       "8                                  NaN   \n",
       "9                                  NaN   \n",
       "10                                 NaN   \n",
       "11                                 NaN   \n",
       "12                                 NaN   \n",
       "13                                 NaN   \n",
       "14                                 NaN   \n",
       "15                                 NaN   \n",
       "\n",
       "title    3.091x: Introduction to Solid State Chemistry  \\\n",
       "user_id                                                  \n",
       "1                                                  NaN   \n",
       "2                                                  NaN   \n",
       "3                                                  NaN   \n",
       "4                                                  NaN   \n",
       "5                                                  NaN   \n",
       "6                                                  NaN   \n",
       "7                                                  NaN   \n",
       "8                                                  NaN   \n",
       "9                                                  NaN   \n",
       "10                                                 NaN   \n",
       "11                                                 NaN   \n",
       "12                                                 NaN   \n",
       "13                                                 NaN   \n",
       "14                                                 NaN   \n",
       "15                                                 NaN   \n",
       "\n",
       "title    6.002x: Circuits and Electronics  \\\n",
       "user_id                                     \n",
       "1                                     NaN   \n",
       "2                                     NaN   \n",
       "3                                     NaN   \n",
       "4                                     NaN   \n",
       "5                                     NaN   \n",
       "6                                       5   \n",
       "7                                     NaN   \n",
       "8                                     NaN   \n",
       "9                                     NaN   \n",
       "10                                    NaN   \n",
       "11                                    NaN   \n",
       "12                                    NaN   \n",
       "13                                    NaN   \n",
       "14                                    NaN   \n",
       "15                                    NaN   \n",
       "\n",
       "title    6.00x: Introduction to Computer Science and Programming  \\\n",
       "user_id                                                            \n",
       "1                                                      NaN         \n",
       "2                                                      NaN         \n",
       "3                                                      NaN         \n",
       "4                                                      NaN         \n",
       "5                                                      NaN         \n",
       "6                                                      NaN         \n",
       "7                                                      NaN         \n",
       "8                                                      NaN         \n",
       "9                                                      NaN         \n",
       "10                                                     NaN         \n",
       "11                                                     NaN         \n",
       "12                                                     NaN         \n",
       "13                                                     NaN         \n",
       "14                                                     NaN         \n",
       "15                                                     NaN         \n",
       "\n",
       "title    7.00x: Introduction to Biology - The Secret of Life  \\\n",
       "user_id                                                        \n",
       "1                                                      NaN     \n",
       "2                                                      NaN     \n",
       "3                                                      NaN     \n",
       "4                                                      NaN     \n",
       "5                                                      NaN     \n",
       "6                                                      NaN     \n",
       "7                                                      NaN     \n",
       "8                                                      NaN     \n",
       "9                                                      NaN     \n",
       "10                                                     NaN     \n",
       "11                                                     NaN     \n",
       "12                                                     NaN     \n",
       "13                                                     NaN     \n",
       "14                                                     NaN     \n",
       "15                                                     NaN     \n",
       "\n",
       "title    8.02x: Electricity and Magnetism  8.MReVx: Mechanics ReView  \\\n",
       "user_id                                                                \n",
       "1                                     NaN                        NaN   \n",
       "2                                     NaN                        NaN   \n",
       "3                                     NaN                        NaN   \n",
       "4                                     NaN                        NaN   \n",
       "5                                     NaN                        NaN   \n",
       "6                                     NaN                        NaN   \n",
       "7                                     NaN                        NaN   \n",
       "8                                     NaN                        NaN   \n",
       "9                                     NaN                        NaN   \n",
       "10                                    NaN                        NaN   \n",
       "11                                    NaN                        NaN   \n",
       "12                                    NaN                        NaN   \n",
       "13                                    NaN                        NaN   \n",
       "14                                    NaN                        NaN   \n",
       "15                                    NaN                        NaN   \n",
       "\n",
       "title    A Beginner&#39;s Guide to Irrational Behavior  \\\n",
       "user_id                                                  \n",
       "1                                                  NaN   \n",
       "2                                                  NaN   \n",
       "3                                                  NaN   \n",
       "4                                                  NaN   \n",
       "5                                                  NaN   \n",
       "6                                                  NaN   \n",
       "7                                                  NaN   \n",
       "8                                                  NaN   \n",
       "9                                                  NaN   \n",
       "10                                                 NaN   \n",
       "11                                                 NaN   \n",
       "12                                                 NaN   \n",
       "13                                                 NaN   \n",
       "14                                                 NaN   \n",
       "15                                                 NaN   \n",
       "\n",
       "title    A Crash Course on Creativity  A History of the World since 1300  \\\n",
       "user_id                                                                    \n",
       "1                                 NaN                                NaN   \n",
       "2                                 NaN                                NaN   \n",
       "3                                 NaN                                NaN   \n",
       "4                                 NaN                                NaN   \n",
       "5                                 NaN                                NaN   \n",
       "6                                 NaN                                NaN   \n",
       "7                                 NaN                                NaN   \n",
       "8                                 NaN                                NaN   \n",
       "9                                 NaN                                NaN   \n",
       "10                                NaN                                NaN   \n",
       "11                                NaN                                NaN   \n",
       "12                                NaN                                NaN   \n",
       "13                                NaN                                NaN   \n",
       "14                                NaN                                NaN   \n",
       "15                                NaN                                NaN   \n",
       "\n",
       "title    A Look at Nuclear Science and Technology  \\\n",
       "user_id                                             \n",
       "1                                             NaN   \n",
       "2                                             NaN   \n",
       "3                                             NaN   \n",
       "4                                             NaN   \n",
       "5                                             NaN   \n",
       "6                                             NaN   \n",
       "7                                             NaN   \n",
       "8                                             NaN   \n",
       "9                                             NaN   \n",
       "10                                            NaN   \n",
       "11                                            NaN   \n",
       "12                                            NaN   \n",
       "13                                            NaN   \n",
       "14                                            NaN   \n",
       "15                                            NaN   \n",
       "\n",
       "title    A New History for a New China, 1700-2000: New Data and New Methods, Part 1  \\\n",
       "user_id                                                                               \n",
       "1                                                      NaN                            \n",
       "2                                                      NaN                            \n",
       "3                                                      NaN                            \n",
       "4                                                      NaN                            \n",
       "5                                                      NaN                            \n",
       "6                                                      NaN                            \n",
       "7                                                      NaN                            \n",
       "8                                                      NaN                            \n",
       "9                                                      NaN                            \n",
       "10                                                     NaN                            \n",
       "11                                                     NaN                            \n",
       "12                                                     NaN                            \n",
       "13                                                     NaN                            \n",
       "14                                                     NaN                            \n",
       "15                                                     NaN                            \n",
       "\n",
       "title    AIDS  Aboriginal Worldviews and Education  \n",
       "user_id                                             \n",
       "1         NaN                                  NaN  \n",
       "2         NaN                                  NaN  \n",
       "3         NaN                                  NaN  \n",
       "4         NaN                                  NaN  \n",
       "5         NaN                                  NaN  \n",
       "6         NaN                                  NaN  \n",
       "7         NaN                                  NaN  \n",
       "8         NaN                                  NaN  \n",
       "9         NaN                                  NaN  \n",
       "10        NaN                                  NaN  \n",
       "11        NaN                                  NaN  \n",
       "12        NaN                                  NaN  \n",
       "13        NaN                                  NaN  \n",
       "14        NaN                                  NaN  \n",
       "15        NaN                                  NaN  "
      ]
     },
     "execution_count": 23,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# transform the ratings frame into a ratings matrix\n",
    "ratings_mtx_df = coursetalk.pivot_table(values='rating',\n",
    "                                             index='user_id',\n",
    "                                             columns='title')\n",
    "ratings_mtx_df.ix[ratings_mtx_df.index[:15], ratings_mtx_df.columns[:15]]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Let's extract only the rating that are 4 or higher."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th>title</th>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <th>A History of the World since 1300</th>\n",
       "      <th>A Look at Nuclear Science and Technology</th>\n",
       "      <th>A New History for a New China, 1700-2000: New Data and New Methods, Part 1</th>\n",
       "      <th>AIDS</th>\n",
       "      <th>Aboriginal Worldviews and Education</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>user_id</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>5</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "title    14.73x: The Challenges of Global Poverty  \\\n",
       "user_id                                             \n",
       "1                                             NaN   \n",
       "2                                             NaN   \n",
       "3                                             NaN   \n",
       "4                                             NaN   \n",
       "5                                             NaN   \n",
       "6                                             NaN   \n",
       "7                                             NaN   \n",
       "8                                             NaN   \n",
       "9                                             NaN   \n",
       "10                                            NaN   \n",
       "11                                            NaN   \n",
       "12                                            NaN   \n",
       "13                                            NaN   \n",
       "14                                            NaN   \n",
       "15                                            NaN   \n",
       "\n",
       "title    2.01x: Elements of Structures  \\\n",
       "user_id                                  \n",
       "1                                  NaN   \n",
       "2                                  NaN   \n",
       "3                                  NaN   \n",
       "4                                  NaN   \n",
       "5                                  NaN   \n",
       "6                                  NaN   \n",
       "7                                  NaN   \n",
       "8                                  NaN   \n",
       "9                                  NaN   \n",
       "10                                 NaN   \n",
       "11                                 NaN   \n",
       "12                                 NaN   \n",
       "13                                 NaN   \n",
       "14                                 NaN   \n",
       "15                                 NaN   \n",
       "\n",
       "title    3.091x: Introduction to Solid State Chemistry  \\\n",
       "user_id                                                  \n",
       "1                                                  NaN   \n",
       "2                                                  NaN   \n",
       "3                                                  NaN   \n",
       "4                                                  NaN   \n",
       "5                                                  NaN   \n",
       "6                                                  NaN   \n",
       "7                                                  NaN   \n",
       "8                                                  NaN   \n",
       "9                                                  NaN   \n",
       "10                                                 NaN   \n",
       "11                                                 NaN   \n",
       "12                                                 NaN   \n",
       "13                                                 NaN   \n",
       "14                                                 NaN   \n",
       "15                                                 NaN   \n",
       "\n",
       "title    6.002x: Circuits and Electronics  \\\n",
       "user_id                                     \n",
       "1                                     NaN   \n",
       "2                                     NaN   \n",
       "3                                     NaN   \n",
       "4                                     NaN   \n",
       "5                                     NaN   \n",
       "6                                       5   \n",
       "7                                     NaN   \n",
       "8                                     NaN   \n",
       "9                                     NaN   \n",
       "10                                    NaN   \n",
       "11                                    NaN   \n",
       "12                                    NaN   \n",
       "13                                    NaN   \n",
       "14                                    NaN   \n",
       "15                                    NaN   \n",
       "\n",
       "title    6.00x: Introduction to Computer Science and Programming  \\\n",
       "user_id                                                            \n",
       "1                                                      NaN         \n",
       "2                                                      NaN         \n",
       "3                                                      NaN         \n",
       "4                                                      NaN         \n",
       "5                                                      NaN         \n",
       "6                                                      NaN         \n",
       "7                                                      NaN         \n",
       "8                                                      NaN         \n",
       "9                                                      NaN         \n",
       "10                                                     NaN         \n",
       "11                                                     NaN         \n",
       "12                                                     NaN         \n",
       "13                                                     NaN         \n",
       "14                                                     NaN         \n",
       "15                                                     NaN         \n",
       "\n",
       "title    7.00x: Introduction to Biology - The Secret of Life  \\\n",
       "user_id                                                        \n",
       "1                                                      NaN     \n",
       "2                                                      NaN     \n",
       "3                                                      NaN     \n",
       "4                                                      NaN     \n",
       "5                                                      NaN     \n",
       "6                                                      NaN     \n",
       "7                                                      NaN     \n",
       "8                                                      NaN     \n",
       "9                                                      NaN     \n",
       "10                                                     NaN     \n",
       "11                                                     NaN     \n",
       "12                                                     NaN     \n",
       "13                                                     NaN     \n",
       "14                                                     NaN     \n",
       "15                                                     NaN     \n",
       "\n",
       "title    8.02x: Electricity and Magnetism  8.MReVx: Mechanics ReView  \\\n",
       "user_id                                                                \n",
       "1                                     NaN                        NaN   \n",
       "2                                     NaN                        NaN   \n",
       "3                                     NaN                        NaN   \n",
       "4                                     NaN                        NaN   \n",
       "5                                     NaN                        NaN   \n",
       "6                                     NaN                        NaN   \n",
       "7                                     NaN                        NaN   \n",
       "8                                     NaN                        NaN   \n",
       "9                                     NaN                        NaN   \n",
       "10                                    NaN                        NaN   \n",
       "11                                    NaN                        NaN   \n",
       "12                                    NaN                        NaN   \n",
       "13                                    NaN                        NaN   \n",
       "14                                    NaN                        NaN   \n",
       "15                                    NaN                        NaN   \n",
       "\n",
       "title    A Beginner&#39;s Guide to Irrational Behavior  \\\n",
       "user_id                                                  \n",
       "1                                                  NaN   \n",
       "2                                                  NaN   \n",
       "3                                                  NaN   \n",
       "4                                                  NaN   \n",
       "5                                                  NaN   \n",
       "6                                                  NaN   \n",
       "7                                                  NaN   \n",
       "8                                                  NaN   \n",
       "9                                                  NaN   \n",
       "10                                                 NaN   \n",
       "11                                                 NaN   \n",
       "12                                                 NaN   \n",
       "13                                                 NaN   \n",
       "14                                                 NaN   \n",
       "15                                                 NaN   \n",
       "\n",
       "title    A Crash Course on Creativity  A History of the World since 1300  \\\n",
       "user_id                                                                    \n",
       "1                                 NaN                                NaN   \n",
       "2                                 NaN                                NaN   \n",
       "3                                 NaN                                NaN   \n",
       "4                                 NaN                                NaN   \n",
       "5                                 NaN                                NaN   \n",
       "6                                 NaN                                NaN   \n",
       "7                                 NaN                                NaN   \n",
       "8                                 NaN                                NaN   \n",
       "9                                 NaN                                NaN   \n",
       "10                                NaN                                NaN   \n",
       "11                                NaN                                NaN   \n",
       "12                                NaN                                NaN   \n",
       "13                                NaN                                NaN   \n",
       "14                                NaN                                NaN   \n",
       "15                                NaN                                NaN   \n",
       "\n",
       "title    A Look at Nuclear Science and Technology  \\\n",
       "user_id                                             \n",
       "1                                             NaN   \n",
       "2                                             NaN   \n",
       "3                                             NaN   \n",
       "4                                             NaN   \n",
       "5                                             NaN   \n",
       "6                                             NaN   \n",
       "7                                             NaN   \n",
       "8                                             NaN   \n",
       "9                                             NaN   \n",
       "10                                            NaN   \n",
       "11                                            NaN   \n",
       "12                                            NaN   \n",
       "13                                            NaN   \n",
       "14                                            NaN   \n",
       "15                                            NaN   \n",
       "\n",
       "title    A New History for a New China, 1700-2000: New Data and New Methods, Part 1  \\\n",
       "user_id                                                                               \n",
       "1                                                      NaN                            \n",
       "2                                                      NaN                            \n",
       "3                                                      NaN                            \n",
       "4                                                      NaN                            \n",
       "5                                                      NaN                            \n",
       "6                                                      NaN                            \n",
       "7                                                      NaN                            \n",
       "8                                                      NaN                            \n",
       "9                                                      NaN                            \n",
       "10                                                     NaN                            \n",
       "11                                                     NaN                            \n",
       "12                                                     NaN                            \n",
       "13                                                     NaN                            \n",
       "14                                                     NaN                            \n",
       "15                                                     NaN                            \n",
       "\n",
       "title    AIDS  Aboriginal Worldviews and Education  \n",
       "user_id                                             \n",
       "1         NaN                                  NaN  \n",
       "2         NaN                                  NaN  \n",
       "3         NaN                                  NaN  \n",
       "4         NaN                                  NaN  \n",
       "5         NaN                                  NaN  \n",
       "6         NaN                                  NaN  \n",
       "7         NaN                                  NaN  \n",
       "8         NaN                                  NaN  \n",
       "9         NaN                                  NaN  \n",
       "10        NaN                                  NaN  \n",
       "11        NaN                                  NaN  \n",
       "12        NaN                                  NaN  \n",
       "13        NaN                                  NaN  \n",
       "14        NaN                                  NaN  \n",
       "15        NaN                                  NaN  "
      ]
     },
     "execution_count": 24,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ratings_gte_4 = ratings_mtx_df[ratings_mtx_df>=4.0]\n",
    "# with an integer axis index only label-based indexing is possible\n",
    "\n",
    "ratings_gte_4.ix[ratings_gte_4.index[:15], ratings_gte_4.columns[:15]]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now picking the number of total ratings for each course and the count of ratings 4+ , we can merge them into one DataFrame."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>gte_4</th>\n",
       "      <th>total</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>title</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <td>2</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <td>15</td>\n",
       "      <td>21</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <td>3</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <td>2</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <td>146</td>\n",
       "      <td>147</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <td>2</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                                    gte_4  total\n",
       "title                                                           \n",
       "14.73x: The Challenges of Global Poverty                2      2\n",
       "2.01x: Elements of Structures                           2      2\n",
       "3.091x: Introduction to Solid State Chemistry           2      3\n",
       "6.002x: Circuits and Electronics                       10     10\n",
       "6.00x: Introduction to Computer Science and Pro...     15     21\n",
       "7.00x: Introduction to Biology - The Secret of ...      3      3\n",
       "8.02x: Electricity and Magnetism                        2      3\n",
       "8.MReVx: Mechanics ReView                               1      1\n",
       "A Beginner&#39;s Guide to Irrational Behavior         146    147\n",
       "A Crash Course on Creativity                            2      5"
      ]
     },
     "execution_count": 25,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ratings_gte_4_pd = pd.DataFrame({'total': ratings_mtx_df.count(), 'gte_4': ratings_gte_4.count()})\n",
    "ratings_gte_4_pd.head(10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>gte_4</th>\n",
       "      <th>total</th>\n",
       "      <th>gte_4_ratio</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>title</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>1.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <td>2</td>\n",
       "      <td>2</td>\n",
       "      <td>1.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <td>2</td>\n",
       "      <td>3</td>\n",
       "      <td>0.666667</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>1.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <td>15</td>\n",
       "      <td>21</td>\n",
       "      <td>0.714286</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <td>3</td>\n",
       "      <td>3</td>\n",
       "      <td>1.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <td>2</td>\n",
       "      <td>3</td>\n",
       "      <td>0.666667</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>1.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <td>146</td>\n",
       "      <td>147</td>\n",
       "      <td>0.993197</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <td>2</td>\n",
       "      <td>5</td>\n",
       "      <td>0.400000</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                                    gte_4  total  gte_4_ratio\n",
       "title                                                                        \n",
       "14.73x: The Challenges of Global Poverty                2      2     1.000000\n",
       "2.01x: Elements of Structures                           2      2     1.000000\n",
       "3.091x: Introduction to Solid State Chemistry           2      3     0.666667\n",
       "6.002x: Circuits and Electronics                       10     10     1.000000\n",
       "6.00x: Introduction to Computer Science and Pro...     15     21     0.714286\n",
       "7.00x: Introduction to Biology - The Secret of ...      3      3     1.000000\n",
       "8.02x: Electricity and Magnetism                        2      3     0.666667\n",
       "8.MReVx: Mechanics ReView                               1      1     1.000000\n",
       "A Beginner&#39;s Guide to Irrational Behavior         146    147     0.993197\n",
       "A Crash Course on Creativity                            2      5     0.400000"
      ]
     },
     "execution_count": 26,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ratings_gte_4_pd['gte_4_ratio'] = (ratings_gte_4_pd['gte_4'] * 1.0)/ ratings_gte_4_pd.total\n",
    "ratings_gte_4_pd.head(10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Functional Programming Principles in Scala 31 31 1.0\n",
      "Introduction to Computer Science 24 24 1.0\n",
      "Programming Languages 24 24 1.0\n",
      "Web Development 16 16 1.0\n",
      "6.002x: Circuits and Electronics 10 10 1.0\n",
      "Compilers 8 8 1.0\n",
      "Archaeology&#39;s Dirty Little Secrets 7 7 1.0\n",
      "How to Build a Startup 7 7 1.0\n",
      "Introduction to Sociology 7 7 1.0\n",
      "Stat2.1X: Introduction to Statistics: Descriptive Statistics 7 7 1.0\n"
     ]
    }
   ],
   "source": [
    "ranking = [(title,total,gte_4, score) for title, total, gte_4, score in ratings_gte_4_pd.itertuples()]\n",
    "\n",
    "for title, total, gte_4, score in sorted(ranking, key=lambda x: (x[3], x[2], x[1])  , reverse=True)[:10]:\n",
    "    print title, total, gte_4, score"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Let's now go easy. Let's count the number of ratings for each course, and order with the most number of ratings.\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "title\n",
       "An Introduction to Interactive Programming in Python    575\n",
       "Design: Creation of Artifacts in Society                191\n",
       "A Beginner&#39;s Guide to Irrational Behavior           147\n",
       "Modern &amp; Contemporary American Poetry               132\n",
       "An Introduction to Operations Management                 98\n",
       "Greek and Roman Mythology                                81\n",
       "Critical Thinking in Global Challenges                   65\n",
       "Gamification                                             54\n",
       "Machine Learning                                         50\n",
       "Web Intelligence and Big Data                            43\n",
       "dtype: int64"
      ]
     },
     "execution_count": 28,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ratings_by_title = coursetalk.groupby('title').size()\n",
    "ratings_by_title.order(ascending=False)[:10]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Considering this information we can sort by the most rated ones with highest percentage of 4+ ratings."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "An Introduction to Interactive Programming in Python 572 575 0.994782608696\n",
      "Design: Creation of Artifacts in Society 190 191 0.994764397906\n",
      "A Beginner&#39;s Guide to Irrational Behavior 146 147 0.993197278912\n",
      "Modern &amp; Contemporary American Poetry 130 132 0.984848484848\n",
      "An Introduction to Operations Management 96 98 0.979591836735\n",
      "Greek and Roman Mythology 80 81 0.987654320988\n",
      "Critical Thinking in Global Challenges 47 65 0.723076923077\n",
      "Gamification 52 54 0.962962962963\n",
      "Machine Learning 48 49 0.979591836735\n",
      "Web Intelligence and Big Data 26 43 0.604651162791\n"
     ]
    }
   ],
   "source": [
    "for title, total, gte_4, score in sorted(ranking, key=lambda x: (x[2], x[3], x[1])  , reverse=True)[:10]:\n",
    "    print title, total, gte_4, score"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Finally using the formula above that we learned, let's find out what the courses that most often occur wit the popular MOOC An introduction to Interactive Programming with Python by using the method \"x + y/ x\" .  For each course, calculate the percentage of Programming with python raters who also rated that course. Order with the highest percentage first, and voilá we have the top 5 moocs."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th>user_id</th>\n",
       "      <th>1</th>\n",
       "      <th>2</th>\n",
       "      <th>3</th>\n",
       "      <th>4</th>\n",
       "      <th>5</th>\n",
       "      <th>6</th>\n",
       "      <th>7</th>\n",
       "      <th>8</th>\n",
       "      <th>9</th>\n",
       "      <th>10</th>\n",
       "      <th>11</th>\n",
       "      <th>12</th>\n",
       "      <th>13</th>\n",
       "      <th>14</th>\n",
       "      <th>15</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>title</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>5</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A History of the World since 1300</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Look at Nuclear Science and Technology</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A New History for a New China, 1700-2000: New Data and New Methods, Part 1</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AIDS</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Aboriginal Worldviews and Education</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "user_id                                             1   2   3   4   5   6   \\\n",
       "title                                                                        \n",
       "14.73x: The Challenges of Global Poverty           NaN NaN NaN NaN NaN NaN   \n",
       "2.01x: Elements of Structures                      NaN NaN NaN NaN NaN NaN   \n",
       "3.091x: Introduction to Solid State Chemistry      NaN NaN NaN NaN NaN NaN   \n",
       "6.002x: Circuits and Electronics                   NaN NaN NaN NaN NaN   5   \n",
       "6.00x: Introduction to Computer Science and Pro... NaN NaN NaN NaN NaN NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ... NaN NaN NaN NaN NaN NaN   \n",
       "8.02x: Electricity and Magnetism                   NaN NaN NaN NaN NaN NaN   \n",
       "8.MReVx: Mechanics ReView                          NaN NaN NaN NaN NaN NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior      NaN NaN NaN NaN NaN NaN   \n",
       "A Crash Course on Creativity                       NaN NaN NaN NaN NaN NaN   \n",
       "A History of the World since 1300                  NaN NaN NaN NaN NaN NaN   \n",
       "A Look at Nuclear Science and Technology           NaN NaN NaN NaN NaN NaN   \n",
       "A New History for a New China, 1700-2000: New D... NaN NaN NaN NaN NaN NaN   \n",
       "AIDS                                               NaN NaN NaN NaN NaN NaN   \n",
       "Aboriginal Worldviews and Education                NaN NaN NaN NaN NaN NaN   \n",
       "\n",
       "user_id                                             7   8   9   10  11  12  \\\n",
       "title                                                                        \n",
       "14.73x: The Challenges of Global Poverty           NaN NaN NaN NaN NaN NaN   \n",
       "2.01x: Elements of Structures                      NaN NaN NaN NaN NaN NaN   \n",
       "3.091x: Introduction to Solid State Chemistry      NaN NaN NaN NaN NaN NaN   \n",
       "6.002x: Circuits and Electronics                   NaN NaN NaN NaN NaN NaN   \n",
       "6.00x: Introduction to Computer Science and Pro... NaN NaN NaN NaN NaN NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ... NaN NaN NaN NaN NaN NaN   \n",
       "8.02x: Electricity and Magnetism                   NaN NaN NaN NaN NaN NaN   \n",
       "8.MReVx: Mechanics ReView                          NaN NaN NaN NaN NaN NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior      NaN NaN NaN NaN NaN NaN   \n",
       "A Crash Course on Creativity                       NaN NaN NaN NaN NaN NaN   \n",
       "A History of the World since 1300                  NaN NaN NaN NaN NaN NaN   \n",
       "A Look at Nuclear Science and Technology           NaN NaN NaN NaN NaN NaN   \n",
       "A New History for a New China, 1700-2000: New D... NaN NaN NaN NaN NaN NaN   \n",
       "AIDS                                               NaN NaN NaN NaN NaN NaN   \n",
       "Aboriginal Worldviews and Education                NaN NaN NaN NaN NaN NaN   \n",
       "\n",
       "user_id                                             13  14  15  \n",
       "title                                                           \n",
       "14.73x: The Challenges of Global Poverty           NaN NaN NaN  \n",
       "2.01x: Elements of Structures                      NaN NaN NaN  \n",
       "3.091x: Introduction to Solid State Chemistry      NaN NaN NaN  \n",
       "6.002x: Circuits and Electronics                   NaN NaN NaN  \n",
       "6.00x: Introduction to Computer Science and Pro... NaN NaN NaN  \n",
       "7.00x: Introduction to Biology - The Secret of ... NaN NaN NaN  \n",
       "8.02x: Electricity and Magnetism                   NaN NaN NaN  \n",
       "8.MReVx: Mechanics ReView                          NaN NaN NaN  \n",
       "A Beginner&#39;s Guide to Irrational Behavior      NaN NaN NaN  \n",
       "A Crash Course on Creativity                       NaN NaN NaN  \n",
       "A History of the World since 1300                  NaN NaN NaN  \n",
       "A Look at Nuclear Science and Technology           NaN NaN NaN  \n",
       "A New History for a New China, 1700-2000: New D... NaN NaN NaN  \n",
       "AIDS                                               NaN NaN NaN  \n",
       "Aboriginal Worldviews and Education                NaN NaN NaN  "
      ]
     },
     "execution_count": 31,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "course_users = coursetalk.pivot_table('rating', index='title', columns='user_id')\n",
    "course_users.ix[course_users.index[:15], course_users.columns[:15]]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "First, let's get only the users that rated the course An Introduction to Interactive Programming in Python"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "ratings_by_course = coursetalk[coursetalk.title == 'An Introduction to Interactive Programming in Python']\n",
    "ratings_by_course.set_index('user_id', inplace=True)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now, for all other courses let's filter out only the ratings from users that  rated the Python course."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th>user_id</th>\n",
       "      <th>1</th>\n",
       "      <th>2</th>\n",
       "      <th>3</th>\n",
       "      <th>4</th>\n",
       "      <th>5</th>\n",
       "      <th>6</th>\n",
       "      <th>7</th>\n",
       "      <th>8</th>\n",
       "      <th>9</th>\n",
       "      <th>10</th>\n",
       "      <th>11</th>\n",
       "      <th>12</th>\n",
       "      <th>13</th>\n",
       "      <th>14</th>\n",
       "      <th>15</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>title</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>14.73x: The Challenges of Global Poverty</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2.01x: Elements of Structures</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3.091x: Introduction to Solid State Chemistry</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.002x: Circuits and Electronics</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>5</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6.00x: Introduction to Computer Science and Programming</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7.00x: Introduction to Biology - The Secret of Life</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.02x: Electricity and Magnetism</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8.MReVx: Mechanics ReView</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Beginner&amp;#39;s Guide to Irrational Behavior</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Crash Course on Creativity</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A History of the World since 1300</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A Look at Nuclear Science and Technology</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>A New History for a New China, 1700-2000: New Data and New Methods, Part 1</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AIDS</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>Aboriginal Worldviews and Education</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "user_id                                             1   2   3   4   5   6   \\\n",
       "title                                                                        \n",
       "14.73x: The Challenges of Global Poverty           NaN NaN NaN NaN NaN NaN   \n",
       "2.01x: Elements of Structures                      NaN NaN NaN NaN NaN NaN   \n",
       "3.091x: Introduction to Solid State Chemistry      NaN NaN NaN NaN NaN NaN   \n",
       "6.002x: Circuits and Electronics                   NaN NaN NaN NaN NaN   5   \n",
       "6.00x: Introduction to Computer Science and Pro... NaN NaN NaN NaN NaN NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ... NaN NaN NaN NaN NaN NaN   \n",
       "8.02x: Electricity and Magnetism                   NaN NaN NaN NaN NaN NaN   \n",
       "8.MReVx: Mechanics ReView                          NaN NaN NaN NaN NaN NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior      NaN NaN NaN NaN NaN NaN   \n",
       "A Crash Course on Creativity                       NaN NaN NaN NaN NaN NaN   \n",
       "A History of the World since 1300                  NaN NaN NaN NaN NaN NaN   \n",
       "A Look at Nuclear Science and Technology           NaN NaN NaN NaN NaN NaN   \n",
       "A New History for a New China, 1700-2000: New D... NaN NaN NaN NaN NaN NaN   \n",
       "AIDS                                               NaN NaN NaN NaN NaN NaN   \n",
       "Aboriginal Worldviews and Education                NaN NaN NaN NaN NaN NaN   \n",
       "\n",
       "user_id                                             7   8   9   10  11  12  \\\n",
       "title                                                                        \n",
       "14.73x: The Challenges of Global Poverty           NaN NaN NaN NaN NaN NaN   \n",
       "2.01x: Elements of Structures                      NaN NaN NaN NaN NaN NaN   \n",
       "3.091x: Introduction to Solid State Chemistry      NaN NaN NaN NaN NaN NaN   \n",
       "6.002x: Circuits and Electronics                   NaN NaN NaN NaN NaN NaN   \n",
       "6.00x: Introduction to Computer Science and Pro... NaN NaN NaN NaN NaN NaN   \n",
       "7.00x: Introduction to Biology - The Secret of ... NaN NaN NaN NaN NaN NaN   \n",
       "8.02x: Electricity and Magnetism                   NaN NaN NaN NaN NaN NaN   \n",
       "8.MReVx: Mechanics ReView                          NaN NaN NaN NaN NaN NaN   \n",
       "A Beginner&#39;s Guide to Irrational Behavior      NaN NaN NaN NaN NaN NaN   \n",
       "A Crash Course on Creativity                       NaN NaN NaN NaN NaN NaN   \n",
       "A History of the World since 1300                  NaN NaN NaN NaN NaN NaN   \n",
       "A Look at Nuclear Science and Technology           NaN NaN NaN NaN NaN NaN   \n",
       "A New History for a New China, 1700-2000: New D... NaN NaN NaN NaN NaN NaN   \n",
       "AIDS                                               NaN NaN NaN NaN NaN NaN   \n",
       "Aboriginal Worldviews and Education                NaN NaN NaN NaN NaN NaN   \n",
       "\n",
       "user_id                                             13  14  15  \n",
       "title                                                           \n",
       "14.73x: The Challenges of Global Poverty           NaN NaN NaN  \n",
       "2.01x: Elements of Structures                      NaN NaN NaN  \n",
       "3.091x: Introduction to Solid State Chemistry      NaN NaN NaN  \n",
       "6.002x: Circuits and Electronics                   NaN NaN NaN  \n",
       "6.00x: Introduction to Computer Science and Pro... NaN NaN NaN  \n",
       "7.00x: Introduction to Biology - The Secret of ... NaN NaN NaN  \n",
       "8.02x: Electricity and Magnetism                   NaN NaN NaN  \n",
       "8.MReVx: Mechanics ReView                          NaN NaN NaN  \n",
       "A Beginner&#39;s Guide to Irrational Behavior      NaN NaN NaN  \n",
       "A Crash Course on Creativity                       NaN NaN NaN  \n",
       "A History of the World since 1300                  NaN NaN NaN  \n",
       "A Look at Nuclear Science and Technology           NaN NaN NaN  \n",
       "A New History for a New China, 1700-2000: New D... NaN NaN NaN  \n",
       "AIDS                                               NaN NaN NaN  \n",
       "Aboriginal Worldviews and Education                NaN NaN NaN  "
      ]
     },
     "execution_count": 33,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "their_ids = ratings_by_course.index\n",
    "their_ratings = course_users[their_ids]\n",
    "course_users[their_ids].ix[course_users[their_ids].index[:15], course_users[their_ids].columns[:15]]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "By applying the division: number of ratings who rated Python Course and the given course / total of ratings who rated the Python Course we have  our percentage."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "course_count =  their_ratings.ix['An Introduction to Interactive Programming in Python'].count()\n",
    "sims = their_ratings.apply(lambda profile: profile.count() / float(course_count) , axis=1)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Ordering by the score, highest first excepts the first one which contains the course itself."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 35,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "title\n",
       "Cryptography I                             0.006957\n",
       "Machine Learning                           0.006957\n",
       "CS-169.1x: Software as a Service           0.005217\n",
       "Python                                     0.005217\n",
       "Introduction to Computer Science           0.005217\n",
       "Human-Computer Interaction                 0.005217\n",
       "Computational Investing, Part I            0.005217\n",
       "Learn to Program: Crafting Quality Code    0.005217\n",
       "Web Development                            0.005217\n",
       "Gamification                               0.005217\n",
       "dtype: float64"
      ]
     },
     "execution_count": 35,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "sims.order(ascending=False)[1:][:10]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 2",
   "language": "python",
   "name": "python2"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 2
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython2",
   "version": "2.7.10"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 0
}