Crime events are not random. They cluster in space.
In other words, certain blocks, neighborhoods, and cities have higher crime rates than others.
The goal of spatial analysis of crime is not just to display where crimes occur but to understand why crimes occur where they do- and more specifically, why crime rates cluster where they do.
Criminologists who spatially analyze crime rates examine various characteristics of areas--most frequently factors such as poverty, racial/ethnic composition, and land use--in order to determine if these factors play a role in predicting where crime is more likely to happen.
The fundamental question we seek to answer is: how do the social and physical characteristics of locations relate to the levels of crime in those areas?
2011 is the most recent year for which he have the most crime data for our range of cities in the Southern California region.
The 1/2 mile radius represent the common distance people will walk to various amenities. A 2-mile radius is useful since it gives a broader perspective (e.g., of where people drive) so the two can be compared.
Currently, we do not have crime data for every single city in the Southern California region (although we have the majority of cities).The cities for which we have crime data are outlined in blue.