There were substantial fluctuations in the numbers of American overseas travelers, especially before World War II. These fluctuations in travel around the robust, long term upward trend are the focus of this paper. We first identify those fluctuations in the raw data and then try to explain the...

This paper proposes a simple theory of a system of cities that decomposes the determinants of the city size distribution into three main components: efficiency, amenities, and frictions. Higher efficiency and better amenities lead to larger cities, but also to greater frictions through...

Several Chinese cities have invested billions of dollars to construct new industrial parks. These place based investments solve the land assembly problem which allows many productive firms to co-locate close to each other. The resulting local economic growth creates new opportunities for real...

Should the national government undertake policies aimed at strengthening the economies of particular localities or regions? Agglomeration economies and human capital spillovers suggest that such policies could enhance welfare. However, the mere existence of agglomeration externalities does not...

Urban economics has traditionally viewed cities as having advantages in production and disadvantages in consumption. We argue that the role of urban density in facilitating consumption is extremely important and understudied. As firms become more mobile, the success of cities hinges more and...

In many cities, restaurants and retail establishments are spatially concentrated. Economists have long recognized the presence of demand externalities that arise from spatial agglomeration as a possible explanation, but empirically identifying this type of spillovers has proven difficult. We...

We document a novel stylized fact: Using data for several countries, we show that export activity is disproportionately concentrated in larger cities - even more so than overall economic activity. We account for this fact by marrying elements of international trade and economic geography. We...

We provide new theory and evidence on the role of consumption access in understanding the agglomeration of economic activity. We combine smartphone data that records user location every 5 minutes of the day with economic census data on the location of service-sector establishments to measure...