---
title: "crime data"
author: "aaron mamula"
date: "11/20/2016"
output: html_document
---


## Data

I was able to compile data on crime from a few different sources.

1. State-level felony crimes are available from the FBI's Uniform Crime Reporting system.  I pull these data directly from Quandl.  The Quandl series for New York is [FBI_UCR/NEW_YORK](https://www.quandl.com/data/FBI_UCR/NEW_YORK-Estimated-Crime-In-New-York)

2. State-level unemployment rates come from the St. Louis Federal Reserve Database (FRED)...but I also pull these using Quandl.  Quandl has these data available from a few different databases (BLS and FRED both supply them).  I prefer pulling from the [FRED database in Quandl]( https://www.quandl.com/data/FRBC/UNEMP_ST_CA-Unemployment-California).

3.  County-by-County population numbers (which are used to normalize crime by population) also come from Quandl.  At the moment I only need these for [New York]((https://www.quandl.com/data/FRED/NYNEWY1POP-Resident-Population-in-New-York-County-NY) and California because those are the only states that I have county-level crime reports. 

4. The remaining data come from a mis-mash of websites where I downloaded individual text files:

* The FBI's UCR allows download of major crimes for big cities.  Frustratingly, I had to pull separately fro cities over 500,000 residents and cities over 1,000,000 residents.  Also frustratingly, I had to choose between getting multiple crime series (aggravated assault, murder, felony larceny, etc) for a single city...or multiple cities for a single crime series.  The text file "data/crime_bigcities_clean" has the "all violent crimes" series for cities over 1,000,000 resident from 1985-2012.

* The text file "data/LocalCrime.csv" has the series "all violent crime" for cities over 500,000 residents from 1985 to 2012.

* The data on number of police employed by state over time (which shows up as an explanatory/control variable in several of the "broken windows" regression studies) was a real pain in the ass to get.  I'm still looking for better data on this variable.  Currently, I have number of police employed from the BEA's Quarterly Census of Employment and Wages, which I queried for individual states.  The available time-series that I found only spanned 2005 - 2015.  

  * these files are named things like "data/ma_police.csv" for MA
  * "data/nj_police.csv" for NJ
  * "data/ohio_police.csv"

* Finally, the two county-level crime data sets I found are

  * California: "data/CA_arrest_data_2005-2014.csv"...in order to make sense of these you will also need the list of arrest codes I downloaded from the California Attorney General's Office: "data/arrest_offense_codes.pdf"
  * New York: "data/arrests_NY.txt".  These data are more plug-and-play than the CA data.