Alfred Marshall argues that industrial agglomerations exist in part because individuals can" learn skills from each other when they live and work in close proximity to one another. An" increasing amount of evidence suggests that the informational role of cities is a primary reason for" their...

Are the well-known facts about urbanization in the United States also true for the developing world? We compare American metropolitan areas with comparable geographic units in Brazil, China and India. Both Gibrat's Law and Zipf's Law seem to hold as well in Brazil as in the U.S., but China and...