Historically, urban growth required enough development to grow and transport significant agricultural surpluses or a government effective enough to build an empire. But there has been an explosion of poor mega-cities over the last thirty years. A simple urban model illustrates that in closed...

Should China build mega-cities or a network of linked middle-sized metropolises? Can Europe's mid-sized cities compete with global agglomeration by forging stronger inter-urban links? This paper examines these questions within a model of recombinant growth and endogenous local amenities. Three...

We study the local effects of a federal program that helped cities clear areas for redevelopment, rehabilitate structures, complete city plans, and enforce building codes. We use an instrumental variable strategy to estimate the program's effects on city-level measures of income, property...

In Beijing, the metropolitan government has made enormous place based investments to increase green space and to improve public transit. We examine the gentrification consequences of such public investments. Using unique geocoded real estate and restaurant data, we document that the construction...

We study the urban structure of the City of Detroit. Following several decades of decline, the city's current urban structure is clearly not optimal for its size, with a business district immediately surrounded by a ring of largely vacant neighborhoods. We propose a model with residential...

We exploit regional variation in suitability for cultivating potatoes, together with time variation arising from their introduction to the Old World from the Americas, to estimate the impact of potatoes on Old World population and urbanization. Our results show that the introduction of the...

Buenos Aires and Chicago grew during the nineteenth century for remarkably similar reasons. Both cities were conduits for moving meat and grain from fertile hinterlands to eastern markets. However, despite their initial similarities, Chicago was vastly more prosperous for most of the 20th...

At the metropolitan level there is a striking negative correlation between residential racial segregation and population characteristics -- particularly for black residents -- but it is widely recognized that this correlation may not be causal. This paper provides a novel test of the causal...

Cost savings associated with increased gasoline prices and lower levels of urban sprawl have been cited in terms of personal savings, environmental awareness, reduced costs through lower travel times and congestion, and reduced income inequality. Cost savings in terms of improved health,...

Africa is urbanizing rapidly, and this creates both opportunities and challenges. Labor productivity appears to be much higher in developing-world cities than in rural areas, and historically urbanization is strongly correlated with economic growth. Education seems to be a strong complement to...