In the Southern California Crime Study (SCCS), the researchers made an effort to contact each police agency in the Southern California region and request address-level incident crime data for the years 2005-2012. Many of the agencies were willing to share their data with us. As a consequence, we have crime data for 2,740 of the 3,852 tracts in the region, which cover 219 of the 341 cities and 83.3 percent of the region’s population.
. The data come from crime reports officially coded and reported by the police departments. We classified crime events into six Uniform Crime Report (UCR) categories: homicide, aggravated assault, robbery, burglary, motor vehicle theft, and larceny. Crime events were geocoded for each city separately to latitude–longitude point locations using ArcGIS 10.2, and subsequently aggregated to various units such as blocks, block groups, and census tracts. The average geocoding match rate was 97.2% across the cities, with the lowest value at 91.4%. These data have been used in several prior studies (Kubrin and Hipp 2016; Hipp and Kubrin Forthcoming).