When there are binding price controls, there are shortages and the allocation of goods across consumers may not be efficient. In general, the misallocation costs of price controls are first order, while the classic welfare losses due to undersupply are second order. This paper presents an...

Urban economists understand housing prices with a spatial equilibrium approach that assumes people must be indifferent across locations. Since the spatial no arbitrage condition is inherently imprecise, other economists have turned to different no arbitrage conditions, such as the prediction...

In Manhattan and elsewhere, housing prices have soared over the 1990s. Rising incomes, lower interest rates, and other factors can explain the demand side of this increase, but some sluggishness on the supply of apartment buildings also is needed to account for the high and rising prices. In a...

The 1990s were an unusually good decade for the largest American cities and, in particular, for the cities of the Midwest. However, fundamentally urban growth in the 1990s looked extremely similar to urban growth during the prior post-war decades. The growth of cities was determined by three...

This paper discusses the prevalence of Silicon Valley-style localizations of individual manufacturing industries in the United States. Several models in which firms choose locations by throwing darts at a map are used to test whether the degree of localization is greater than would be expected...

How effective are restrictions on mobility in limiting COVID-19 spread? Using zip code data across five U.S. cities, we estimate that total cases per capita decrease by 20% for every ten percentage point fall in mobility. Addressing endogeneity concerns, we instrument for travel by residential...

Do urban children live more segregated lives than urban adults? Using cellphone location data and following the 'experienced isolation' methodology of Athey et al. (2021), we compare the isolation of students over the age of 16--who we identify based on their time spent at a high school--and...

Empirical research on cities starts with a spatial equilibrium condition: workers and firms are assumed to be indifferent across space. This condition implies that research on cities is different from research on countries, and that work on places within countries needs to consider population,...

Recent literature on the relationship between ethnic or racial segregation and outcomes has failed to produce a consensus view of the role of ghettos; some studies suggest that residence in an enclave is beneficial, some reach the opposite conclusion, and still others imply that any relationship...

In the past few decades, some measures of population risk have improved, while others have deteriorated. Understanding the health of the population requires integrating these different trends. We compare the risk factor profile of the population in the early 1970s with that of the population in...