[Retric]

This is useless for my area 22202 Arlington VA. You basically mark all areas with highrises as red, and areas with single track housing as green. Sorry, if there is a row of 22 story building on one block and 3 blocks away is single family dwellings of course there is going to be more crimes where there is 30x the number of people.

http://www.trulia.com/local/#crimes/washington-dc

PS: http://en.wikipedia.org/wiki/File:ArlingtonTODimage3.jpg High density, mixed use development is often concentrated within 1/4 to 1/2 mile from the County's Metrorail rapid transit stations, such as in Rosslyn, Courthouse, and Clarendon (shown in red from upper left to lower right). http://en.wikipedia.org/wiki/Arlington_County,_Virginia

[sukuriant]

Fair enough. Then make the influence of each crime inversely proportional to the number of people there. All of that said, don't go to the smooth spots of the function that aren't current and declare "this is the crime rate of this place". That was my point