Chicago

Much of the data in the book is from Chicago, and co-author Steven Levitt is a professor at the University of Chicago. For instance, data from the Chicago Public School system is used to support the authors' arguments that high-stakes testing acts as a strong incentive for teachers to cheat, that school choice does not make a difference in school performance and that what a parent does matters less than what a parent is in determining a child's school performance. Chicago is also the home of the Black Gangster Disciple Nation, a drug-dealing gang whose financial records are used to support the authors' argument that, despite the conventional wisdom to the contrary, most drug dealers do not make much money.

New York City

New policing tactics are implemented in the 1990s in New York City by the city's former mayor Rudolph Giuliani and his police commissioner, William...