Sudhir Venkatesh, the amazing sociologist who was my co-author on the gangs research that we write about in Freakonomics, has a great new documentary. It will be showing on WTTW, Chicago’s PBS affiliate at Thursday, Nov. 17th, 9pm Friday, Nov. 18th, 10pm. If you don’t live in Chicago, you are out of luck, at least for now. I have seen . . .