We study why acquisitions of entrant firms by an incumbent can deter innovation and entry in the digital platform industry, where there are strong network externalities and some customers face switching costs. A high probability of an acquisition induces some potential early adopters to wait for...

Health insurers increasingly compete on their covered networks of medical providers. Using data from Massachusetts' pioneer insurance exchange, I find substantial adverse selection against plans covering the most prestigious and expensive “star” hospitals. I highlight a theoretically...

Why was the Black Death followed by the decline of serfdom in Western Europe but its' intensification in Eastern Europe? What explains why involvement in Atlantic trade in the Early Modern period was positively correlated with economic growth in Britain but negatively correlated in Spain? Why...

We argue that the time-varying regional distribution of housing equity influences the aggregate consequences of monetary policy through its effects on mortgage refinancing. Using detailed loan-level data, we show that regional differences in housing equity affect refinancing and spending...

We explore the impact of rising incomes at the top of the distribution on spatial sorting patterns within large U.S. cities. We develop and quantify a spatial model of a city with heterogeneous agents and non-homothetic preferences for neighborhoods with endogenous amenity quality. As the rich...

In this chapter we analyze immigration and its effect on urban and regional economies focusing on productivity and labor markets. While immigration policies are typically national, the effects of international migrants are often more easily identified on local economies. The reason is that their...

How integrated are labor markets within a country? Labor mobility is key to the integration of local labor markets and therefore to understanding the efficacy of policies to reduce regional inequality. We present a comprehensive framework for understanding migration decisions, focusing on the...

We study the distribution of economic activity, as proxied by lights at night, across 250,000 grid cells of average area 560 square kilometers. We first document that nearly half of the variation can be explained by a parsimonious set of physical geography attributes. A full set of country...