This week's map requires a bit of explanation. On the left is a normal neighborhood map of Baltimore. The map at right is a cartogram, with the neighborhoods larger or smaller depending on population (per the 2000 census). The dots represent calls to 311 to report illegal dumping. As you can see, there's a rough correlation between population and illegal dumping calls--so the more people, the more dumping, right? Not so simple. Sarah Williams, director of the Spatial Information Design Lab at Columbia University, who has done some pretty cool analysis of 311 calls for New York City, points out that the calls often tell you more about the callers than whatever they're calling about. In this case, it's possible (likely, even) that the areas with the most dumping calls just have more people to report them.
Disclaimer: What's the 311? is based on data from the Mayor's Office of Information Technology (currently from Sept. 20, 2005, until Jan. 31, 2008). It has been folded, spindled, and mutilated along the way, and no attempt has been made to verify the accuracy of the calls. Thanks to reader C.F. for pointing out that in the last 311 map, Baltimore was accidentally squished into a square. As it happens, we are working on a giant robot to do just that.
