A large literature in cognitive science studies the puzzling "Flynn effect" of rising fluid intelligence (reasoning skill) in rich countries. We develop an economic model in which a cohort's mix of skills is determined by different skills' relative returns in the labor market and by the...

"The controversy over whether and how much to charge for health products in the developing world rests, in part, on whether higher prices can increase use. We test this hypothesis in a field experiment in Zambia using door-to-door marketing of a home water purification solution. Our methodology...