Module 8 Law Enforcemet: Washington DC

The posted maps where completed for the Week 8 activity if the University of West Florida On-Line GIS Certification program class, Applications in GIS (GIS4048). The focus of the week was Law Enforcement and GIS and the goal of the activity was to use GIS to analyze crime and police station data and make recommendations based on the data for adjustments to current patrols.

Maps are being posted now. Background to follow:


The first map is a base map of Washington DC showing the location of police stations and crime incidents that occurred in August 2009.


The next map shows crime proximity to the police stations. The proximity color bands were created using a Multiple Ring Buffer tool to measure proximity at intervals of 0.5, 1.0 and 2.0 Miles from each station.


The third map shows Crime Densities for three specific types of crime: Burglary, Sex Abuse and Homicide. The densities were created using a GIS Spatial Analysis tool called, Kernel Density.


The final map also uses the Kernel Density tool to show a time series snap-shot of auto theft crimes based on when they occur in a 24-hour day.

The biggest issue I had in developing these maps was the slow refresh rate of the computer. For some reason, every adjutment to a map I made required long refresh times. I tried to use the Map Cache toolbar to alleviate the re-draws but it did not seem to be working for me. The lab also included some time savers like saving a Base Map to use over and over again. Unfortunately, I failed to get my basemap set correctly at the beginning based on the later labs so I still ended up with a lot of redo work which was particularly painful in regards to trying to get the road labels to diplay correctly. I did figure out a useful trick though on the fourth map which was that it was just as easy to compy the first data frame with all it's layers in it to three additional layers (then the Frame Properties were already set). I also found it easier to compose the map before adding everything. Finally, I had major problems using the graphing tool on this lab such that I decide it was more effective to export data from the graph tool to an Excel spreadsheet and create the graph there then copy it back to the map. The last two graphs were done using these procedures and they look much better then the first one.