Meanwhile in Chicago...
|Recently, Papachristos followed up with a new investigation, and a much larger new data set: non-fatal gunshot injuries in the city.|
The data in the new paper is equally fascinating, and on one level, as you might expect, quite troubling. To begin with, the dramatic disparities the rates of nonfatal gunshot injury: overall it's 46.5 per 100,000 for the city[Chicago] as a whole from 2006-2012. It's 1.62 per 100,000 for whites; 28.72 for Hispanics, and 112.83 for blacks.
For all males, it's 44.68 per 100,000; 239.77 for black males, and for black males from 18-34 it's 599.65. As Papachristos and co-authors Christopher Wildeman and Elizabeth Roberto point out, that's a staggering one in 200.
The numbers are enormous, and they've caused a lot of pessimism. But the point of digging into the data is to create, literally, maps—to follow the violence through the city and, as maps are meant to do, guide us back to its sources. And in that sense, cohesive patterns emerge.
Papachristos constructs a social network—not a virtual one in the Facebook sense, but a real one of social connections between people—by looking at arrestees who have been arrested together. That turns out to be a lot of people in raw numbers, almost 170,000 people with a "co-offending tie" to one another, with an average age of 25.7 years, 78.6 percent male and 69.5 percent black. It's also a large percentage of all the individuals arrested: 40 percent of all the individuals arrested during that period.
Within the entire group, the largest component of that whole co-offender group has 107,740 people.
Within the timeframe—from 2006 to 2010—70 percent of all shootings in Chicago, or about 7,500 out of over 10,000, are contained within all the co-offending networks. And 89 percent of those shootings are within the largest component.
Or, to put another way: the rate of gunshot victimization (nonfatal + fatal) in Chicago is 62.1 per 100k. Within a co-offending network, it's 740.5—more than 10 times higher.