“For the last decade or so, economists have been increasingly poking their fingers into other disciplines, including epidemiology, psychology, sociology, oenology and even football strategy. These economists usually justify their expansionism on two grounds: They say they’re better with numbers than most other researchers and have a richer understanding of how people respond to incentives. Arrogant as this sounds, there is some truth to it. Besides, the public seems hungry for the kind of real-world social science economists are practicing.”