CrimeStat is a crime mapping software program. CrimeStat is Windows-based program that conducts spatial and statistical analysis and is designed to interface with a geographic information system (GIS). The program is developed by Ned Levine & Associates under the direction of Ned Levine, with funding by the National Institute of Justice (NIJ), an agency of the United States Department of Justice. The program and manual are distributed for free by NIJ.
CrimeStat performs spatial analysis on objects located in a GIS. The objects can be points (e.g., events, locations), zones (e.g., blocks, traffic analysis zones, cities) or lines (e.g., street segments). The program can analyze the distribution of the objects, identify hot spots, indicate spatial autocorrelation, monitor the interaction of events in space and time, and model travel behavior.
There is a regression module for non-linear spatial modeling. Some of its tools are specific to crime analysis. Others can by applied in many fields. There are 55 statistical routines in the program.
Development
CrimeStat has been developed since the mid-1990s under the direction of Ned Levine. The first prototype was a Unix-based C++ program called Pointstat that was developed to analyze motor vehicle crashes in Honolulu. In 1996, the National Institute of Justice funded the first version of CrimeStat and the early Pointstat routines were folded into the program.
The first version (1.0) was released in August 1999: the latest version is 3.3 (July 2010).
Up to version 3.1, CrimeStat was programmed by Long Doan of Doan Consulting, Falls Church, VA. Beginning at version 2.0, and solely from version 3.2, CrimeStat was programmed primarily by Haiyan Teng of Houston, TX.
Functionality
Data setup
CrimeStat can input data both attribute and GIS files but requires that all datasets have geographical coordinates assigned for the objects. The basic file format is dBase (dbf) but shape (shp), and Ascii text files can also be read. The program requires a Primary File but many routines also use a Secondary File. CrimeStat uses three coordinate systems: spherical (longitude, latitude), projected and directional (angles).
Distance can be measured as direct, indirect (Manhattan) or on a network (which also allows travel time or speed to be used). Distance units are decimal degrees for spherical coordinates and feet, meters, miles, kilometers, or nautical miles for projected coordinates. The program can create reference grids. Several routines also use the area of the geographical region for their calculations.
Statistical routines
The spatial description routines include:
Spatial distribution statistics (mean center, standard deviation ellipse, center of minimum distance, median center, directional mean, convex hull) Spatial autocorrelation statistics for zonal data (Moran's I, Getis's G, Getis-Ord Global G, Moran correlogram, Geary correlogram, Getis-Ord correlogram), Distance-based statistics among points (nearest neighbor analysis, Ripley's "K", the allocation and summation of Primary File points to Secondary File points, and various distance calculation matrices), and Cluster analysis statistics for points, zones or lines. CrimeStat has a range of routines available for cluster identification:
Monte Carlo simulations can be run on many routines to estimate credible intervals.
The spatial modeling routines include: