---
layout: post
title: "ISL: Chapter 2"
published: yes
---

## `College`

```{r label="download and read data"}
# fileUrl <- "http://www-bcf.usc.edu/~gareth/ISL/College.csv"
# download.file(fileUrl,destfile="./ISL/College.csv")

college <- read.csv('./ISL/College.csv')
rownames(college)=college[,1]
college=college[,-1]
summary(college)
# pairs(college)
pairs(college[,1:10])
pairs(college[,1:5])
attach(college)
Private <- as.factor(Private)
plot(Private,Outstate,xlab="Private",ylab="Outstate",varwidth=T)
```

```{r label="create Elite"}
Elite=rep("No",nrow(college))
Elite[college$Top10perc > 50]="Yes"
Elite=as.factor(Elite)
college=data.frame(college,Elite)
summary(Elite)
plot(Elite,Outstate,xlab="Elite",ylab="Outstate",varwidth=T)
```

```{r label="histogram"}
par(mfrow=c(2,2))
hist(Books, breaks=30,col=1)
hist(Apps, breaks=30,col=2)
hist(Personal, breaks=30,col=3)
hist(Room.Board, breaks=30,col=4)
```


## `Boston`

```{r label=boston}
library(MASS)
# pairs(Boston)
pairs(Boston[,c(5:8,10:14)])
attach(Boston)
plot(medv,lstat)
plot(medv,rm,col=2,pch=2)
plot(medv,nox,col=4,pch=4)

B8 = Boston[(Boston$rm>8),]
summary(B8)
```