# Data dictionary - The Augmented Synthetic Control Method: The Kansas Tax Cuts

Companion data for a beginner-friendly R tutorial on the <strong>Augmented Synthetic Control Method (ASCM)</strong> of Ben-Michael, Feller &amp; Rothstein (2021), estimating the effect of the May 2012 Kansas personal-income-tax cut on log gross state product (GSP) per capita. The dataset is the <code>kansas</code> object shipped with the <code>augsynth</code> R package: a <strong>balanced</strong> panel of 50 U.S. states observed every quarter from 1990 Q1 to 2016 Q1 (105 quarters per state, 5,250 rows). Kansas (FIPS 20) is the single treated unit, switched on from 2012 Q2 (<code>year_qtr = 2012.25</code>) onward; the other 49 states form the donor pool. The outcome is <code>lngdpcapita</code>; per-capita revenue, wage, establishment and employment series serve as auxiliary covariates. The tutorial moves from classic SCM through ridge augmentation and covariate balancing, then compares four ways to do inference.


Companion data for the post <https://carlos-mendez.org/post/r_augsynth/>. Each dataset ships as a labeled Stata `.dta` (v118) plus its source file. Generated by `build_data_dictionary.py`.

## Data sources

| Source | Provides | Reference / URL |
|---|---|---|
| augsynth R package (kansas) | The full panel — the package&#x27;s bundled kansas object, copied to CSV for reproducibility | Ben-Michael, E. augsynth: Augmented Synthetic Control Method. <a href="https://github.com/ebenmichael/augsynth" target="_blank" rel="noopener">https://github.com/ebenmichael/augsynth</a> |
| BEA / BLS QCEW (underlying) | Gross state product, per-capita revenue, wages, establishments and employment series | U.S. Bureau of Economic Analysis (GSP) and Bureau of Labor Statistics QCEW, as assembled in the augsynth kansas object. |
| Ben-Michael, Feller &amp; Rothstein (2021) | Replicated method (ASCM) and the canonical Kansas application | Ben-Michael, E., Feller, A., &amp; Rothstein, J. (2021). The Augmented Synthetic Control Method. Journal of the American Statistical Association, 116(536), 1789–1803. |
| Method references | Estimators and inference concepts | Abadie, Diamond &amp; Hainmueller (2010); Abadie &amp; Gardeazabal (2003); Chernozhukov, Wüthrich &amp; Zhu (2021). |

## Dataset links (GitHub)

| File | View on GitHub | Raw (load / download) |
|---|---|---|
| `kansas.dta` | [view](https://github.com/cmg777/starter-academic-v501/blob/master/content/post/r_augsynth/data/kansas.dta) | [raw](https://raw.githubusercontent.com/cmg777/starter-academic-v501/master/content/post/r_augsynth/data/kansas.dta) |

## Load in code

```python
import pandas as pd
BASE = "https://raw.githubusercontent.com/cmg777/starter-academic-v501/master/content/post/r_augsynth/data/"
df = pd.read_stata(BASE + "kansas.dta")
```

## Datasets

| File | Grain | Rows x Cols | Purpose |
|---|---|---|---|
| `kansas` | state-quarter | 5,250 x 32 | Estimate the ATT of the 2012 Kansas tax cut via classic SCM, Ridge ASCM and covariate ASCM. |

## Cross-file variable index

| Variable | kansas |
|---|---|
| `abb` | ● |
| `avg_wkly_wage` | ● |
| `avgwklywagecapita` | ● |
| `emplvl1capita` | ● |
| `emplvl2capita` | ● |
| `emplvl3capita` | ● |
| `emplvlcapita` | ● |
| `estabscapita` | ● |
| `fips` | ● |
| `gdp` | ● |
| `gdpcapita` | ● |
| `lngdp` | ● |
| `lngdpcapita` | ● |
| `month1_emplvl` | ● |
| `month2_emplvl` | ● |
| `month3_emplvl` | ● |
| `popestimate` | ● |
| `qtr` | ● |
| `qtrly_estabs_count` | ● |
| `rev_local_total` | ● |
| `rev_state_total` | ● |
| `revenuepop` | ● |
| `revlocalcapita` | ● |
| `revstatecapita` | ● |
| `state` | ● |
| `taxable_qtrly_wages` | ● |
| `taxwagescapita` | ● |
| `total_qtrly_wages` | ● |
| `totalwagescapita` | ● |
| `treated` | ● |
| `year` | ● |
| `year_qtr` | ● |

### `kansas`

| Variable | Label | Definition | Construction | Units | Source | Coverage |
|---|---|---|---|---|---|---|
| `fips` | State FIPS code | Federal Information Processing Standard numeric state identifier (Kansas = 20). | From the augsynth kansas object; the panel unit id. | code | augsynth kansas | 50 states |
| `year` | Calendar year | Year of the observation (1990-2016). | From the kansas object. | year | augsynth kansas |  |
| `qtr` | Calendar quarter (1-4) | Quarter of the year (1 = Q1 ... 4 = Q4). | From the kansas object. | 1-4 | augsynth kansas |  |
| `state` | State name | Full U.S. state name. | From the kansas object. | string | augsynth kansas |  |
| `gdp` | Gross state product (level) | Quarterly gross state product (gross domestic product by state). | From the kansas object (BEA GSP). | US$ (millions) | BEA (via augsynth) |  |
| `revenuepop` | State revenue per capita (annual) | Total state revenue per resident; observed annually only. | From the kansas object; NA in non-reporting quarters. | US$ per capita | augsynth kansas | annual (NA in 3 of 4 quarters) |
| `rev_state_total` | Total state government revenue (annual) | Total state-government revenue for the state-year; observed annually only. | From the kansas object; NA in non-reporting quarters. | US$ | augsynth kansas | annual (NA in 3 of 4 quarters) |
| `rev_local_total` | Total local government revenue (annual) | Total local-government revenue for the state-year; observed annually only. | From the kansas object; NA in non-reporting quarters. | US$ | augsynth kansas | annual (NA in 3 of 4 quarters) |
| `popestimate` | Population estimate | Estimated state resident population for the quarter. | From the kansas object; used as the per-capita denominator. | persons | augsynth kansas |  |
| `qtrly_estabs_count` | Quarterly establishment count | Number of business establishments in the state-quarter (QCEW). | From the kansas object. | establishments | BLS QCEW (via augsynth) |  |
| `month1_emplvl` | Employment level, month 1 of quarter | Employment count in the first month of the quarter (QCEW). | From the kansas object. | persons | BLS QCEW (via augsynth) |  |
| `month2_emplvl` | Employment level, month 2 of quarter | Employment count in the second month of the quarter (QCEW). | From the kansas object. | persons | BLS QCEW (via augsynth) |  |
| `month3_emplvl` | Employment level, month 3 of quarter | Employment count in the third month of the quarter (QCEW). | From the kansas object. | persons | BLS QCEW (via augsynth) |  |
| `total_qtrly_wages` | Total quarterly wages | Total wages paid in the state-quarter (QCEW). | From the kansas object. | US$ | BLS QCEW (via augsynth) |  |
| `taxable_qtrly_wages` | Taxable quarterly wages | Portion of quarterly wages subject to unemployment-insurance tax (QCEW). | From the kansas object. | US$ | BLS QCEW (via augsynth) |  |
| `avg_wkly_wage` | Average weekly wage | Average weekly wage in the state-quarter (QCEW). | From the kansas object. | US$ per week | BLS QCEW (via augsynth) |  |
| `year_qtr` | Decimal year-quarter | Time index as year plus quarter fraction (e.g. 2012.25 = 2012 Q2). | year + (qtr-1)/4; the panel's time variable in augsynth(). | decimal year | Derived |  |
| `treated` | Treated indicator (1 = Kansas post-2012 Q2) | 1 for Kansas (FIPS 20) from 2012 Q2 onward, 0 for all other state-quarters. | Indicator switched on at year_qtr >= 2012.25 for Kansas only. | 0/1 | augsynth kansas |  |
| `gdpcapita` | GSP per capita (level) | Gross state product per resident. | gdp / popestimate (scaled). | US$ per capita | Derived |  |
| `lngdp` | Log gross state product | Natural log of quarterly gross state product. | log(gdp). | log US$ | Derived |  |
| `lngdpcapita` | Log GSP per capita (OUTCOME) | Natural log of gross state product per capita — the study outcome. | log(gdpcapita). | log US$ per capita | Derived |  |
| `revstatecapita` | State revenue per capita (annual) | Total state revenue per resident; annual covariate (log-transformed in the model). | rev_state_total / popestimate; NA in non-reporting quarters. | US$ per capita | Derived | annual (NA in 3 of 4 quarters) |
| `revlocalcapita` | Local revenue per capita (annual) | Total local revenue per resident; annual covariate (log-transformed in the model). | rev_local_total / popestimate; NA in non-reporting quarters. | US$ per capita | Derived | annual (NA in 3 of 4 quarters) |
| `emplvl1capita` | Month-1 employment per capita | First-month employment level as a share of population. | month1_emplvl / popestimate. | ratio | Derived |  |
| `emplvl2capita` | Month-2 employment per capita | Second-month employment level as a share of population. | month2_emplvl / popestimate. | ratio | Derived |  |
| `emplvl3capita` | Month-3 employment per capita | Third-month employment level as a share of population. | month3_emplvl / popestimate. | ratio | Derived |  |
| `emplvlcapita` | Employment per capita (covariate) | Quarterly employment level as a share of population; an ASCM covariate. | Quarterly employment / popestimate. | ratio | Derived |  |
| `totalwagescapita` | Total wages per capita | Total quarterly wages per resident. | total_qtrly_wages / popestimate. | US$ per capita | Derived |  |
| `taxwagescapita` | Taxable wages per capita | Taxable quarterly wages per resident. | taxable_qtrly_wages / popestimate. | US$ per capita | Derived |  |
| `avgwklywagecapita` | Average weekly wage (per-capita covariate) | Average weekly wage used as an ASCM covariate (log-transformed in the model). | From avg_wkly_wage; an auxiliary covariate. | US$ per week | Derived |  |
| `estabscapita` | Establishments per capita (covariate) | Business establishments as a share of population; an ASCM covariate. | qtrly_estabs_count / popestimate. | ratio | Derived |  |
| `abb` | State abbreviation | Two-letter U.S. state postal abbreviation (e.g. KS for Kansas). | From the kansas object. | string | augsynth kansas |  |

| Variable | N | Miss% | Distinct | Min | Mean | Median | Max | SD |
|---|---|---|---|---|---|---|---|---|
| `fips` | 5,250 | 0.0 | 50 | — | — | — | — | — |
| `year` | 5,250 | 0.0 | 27 | 1990 | 2002.6 | 2003 | 2016 | 7.58 |
| `qtr` | 5,250 | 0.0 | 4 | — | — | — | — | — |
| `state` | 5,250 | 0.0 | 50 | — | — | — | — | — |
| `gdp` | 5,250 | 0.0 | 5,227 | 11,509 | 228,237 | 130,650 | 2,568,986 | 298,949 |
| `revenuepop` | 3,000 | 42.9 | 716 | 1,334.6 | 3,851.1 | 3,628.5 | 14,609 | 1,352.8 |
| `rev_state_total` | 2,400 | 54.3 | 600 | 1,667.6 | 20,813 | 13,868 | 182,530 | 24,051 |
| `rev_local_total` | 2,400 | 54.3 | 600 | 550.0 | 17,197 | 10,041 | 143,137 | 23,640 |
| `popestimate` | 5,250 | 0.0 | 5,249 | 453,690 | 5,767,107 | 3,997,978 | 39,250,017 | 6,352,795 |
| `qtrly_estabs_count` | 5,250 | 0.0 | 5,177 | 15,133 | 161,021 | 108,822 | 1,448,488 | 189,559 |
| `month1_emplvl` | 5,250 | 0.0 | 5,240 | 178,737 | 2,482,331 | 1,675,988 | 16,600,851 | 2,656,261 |
| `month2_emplvl` | 5,250 | 0.0 | 5,244 | 178,587 | 2,494,933 | 1,684,341 | 16,633,834 | 2,669,643 |
| `month3_emplvl` | 5,250 | 0.0 | 5,240 | 181,521 | 2,510,204 | 1,699,044 | 16,606,038 | 2,684,404 |
| `total_qtrly_wages` | 5,250 | 0.0 | 5,246 | 881,111,969 | 24,019,317,100 | 13,622,726,754 | 275,326,853,350 | 31,004,422,823 |
| `taxable_qtrly_wages` | 5,250 | 0.0 | 3,051 | 0 | 3,775,737,420 | 1,095,917,898 | 76,893,472,173 | 7,327,919,613 |
| `avg_wkly_wage` | 5,250 | 0.0 | 854 | 301.0 | 674.8 | 658.0 | 1,792.0 | 196.2 |
| `year_qtr` | 5,250 | 0.0 | 105 | 1,990.0 | 2,003.0 | 2,003.0 | 2,016.0 | 7.58 |
| `treated` | 5,250 | 0.0 | 2 | 0 | 0.003 | 0 | 1.00 | 0.055 |
| `gdpcapita` | 5,250 | 0.0 | 5,250 | 15,029 | 37,808 | 36,449 | 84,382 | 12,552 |
| `lngdp` | 5,250 | 0.0 | 5,227 | 9.35 | 11.75 | 11.78 | 14.76 | 1.09 |
| `lngdpcapita` | 5,250 | 0.0 | 5,250 | 9.62 | 10.49 | 10.50 | 11.34 | 0.331 |
| `revstatecapita` | 2,400 | 54.3 | 2,400 | 2,021.3 | 3,741.9 | 3,380.1 | 20,353 | 1,608.9 |
| `revlocalcapita` | 2,400 | 54.3 | 2,400 | 883.6 | 2,480.2 | 2,428.3 | 7,160.9 | 784.0 |
| `emplvl1capita` | 5,250 | 0.0 | 5,250 | 0.325 | 0.437 | 0.436 | 1.05 | 0.041 |
| `emplvl2capita` | 5,250 | 0.0 | 5,250 | 0.325 | 0.439 | 0.438 | 1.05 | 0.040 |
| `emplvl3capita` | 5,250 | 0.0 | 5,250 | 0.329 | 0.442 | 0.441 | 1.05 | 0.041 |
| `emplvlcapita` | 5,250 | 0.0 | 5,250 | 0.327 | 0.439 | 0.438 | 1.05 | 0.041 |
| `totalwagescapita` | 5,250 | 0.0 | 5,250 | 1,492.9 | 3,869.4 | 3,787.3 | 10,275 | 1,216.3 |
| `taxwagescapita` | 5,250 | 0.0 | 3,051 | 0 | 728.8 | 355.7 | 5,254.4 | 924.7 |
| `avgwklywagecapita` | 5,250 | 0.0 | 854 | 301.0 | 674.8 | 658.0 | 1,792.0 | 196.2 |
| `estabscapita` | 5,250 | 0.0 | 5,250 | 0.020 | 0.029 | 0.028 | 0.071 | 0.005 |
| `abb` | 5,250 | 0.0 | 50 | — | — | — | — | — |

## Known limitations & caveats

- <strong>Net effect, not tax-only.</strong> The ATT is the gap between actual Kansas and a synthetic blend; over 2012–2016 Kansas also faced a severe drought and aerospace-sector shocks that SCM cannot strip out separately.
- <strong>Annual revenue series.</strong> <code>rev_state_total</code>, <code>rev_local_total</code>, <code>revenuepop</code>, and the per-capita <code>revstatecapita</code>/<code>revlocalcapita</code> are recorded only once a year and are <code>NA</code> in the other three quarters (2,250–2,850 missing of 5,250).
- <strong>Single treated unit, modest donor pool.</strong> One Kansas and 49 donors limit statistical power; the four inference methods disagree at the margin (jackknife+ excludes zero; conformal p = 0.066; permutation p = 0.10).
- <strong>SCM identifying assumption.</strong> Results rest on a convex (or lightly extrapolated) blend of donors standing in for Kansas's untreated path, and on no donor state being affected by Kansas's policy.

---

*Generated by `build_data_dictionary.py`. Stata format: .dta v118.*
