Jennifer and I were thinking of buying a house in a neighborhood known as Silver Terrace, which we hadn’t heard anything about, so we asked about it on Craigslist and most of the replies warned us that crime there was high. So Jen found the part of the SFPD website (now gone) that had interactive maps that told you the crime rate as of October 2003. It’s difficult to compare various areas, though. You have to click on a high-level city map, which takes you to a low-level map, where you can click on a plot, which takes you to a text page with various crime statistics.
So I wrote a program using Python and the Python Imaging Library that parses the HTML and creates a map with crime highlights.
A few interesting things:
I also had the various breakdown data (violent crime, burglaries, etc.) but I didn’t think it was useful to display it. It’s probably fairly proportional all around. It would be cool to see this over time, say over 30 years. We could also plot the exact locations of registered sex offenders (Megan’s Law), etc. If anyone knows where I can find more raw data, please let me know. It’d make a useful applet.
(Technical notes: The original website broke the city in 16 sub-maps, hence the seams. The thick red lines are district lines. The plot contours were taken from the clickable maps’ <area> tags, some of which were of type RECT and some were POLY.)