I am an Associate Professor of Economics at the University of Chicago Booth School of Business and a Faculty Research Fellow at the National Bureau of Economic Research. My research agenda focuses on the spatial distribution of economic activities across neighborhoods, cities, and countries. I try to understand the substantial variation in the amount and nature of economic activity across space. Recently, I have examined quality specialization in US manufacturing, segregation of urban consumption, and how the global climate affects agricultural trade. At Booth, I teach Managing the Firm in the Global Economy.
Why do high-income countries export high-quality goods: home demand or factor abundance? I develop a model nesting both hypotheses and employ microdata on US manufacturing plants' shipments and factor inputs to quantify the two mechanisms' roles in quality specialization across US cities. Home-market demand explains as much of the relationship between income and quality as differences in factor usage.
We develop the first system-of-cities model with costly idea exchange as the agglomeration force. The model replicates a broad set of established facts about the cross section of cities. It provides the first spatial equilibrium theory of why skill premia are higher in larger cities and how variation in these premia emerges from symmetric fundamentals.
We measure ethnic and racial segregation in urban consumption using Yelp reviews of NYC restaurants. Spatial frictions cause consumption segregation to partly reflect residential segregation. Social frictions also matter: individuals are less likely to visit restaurants in neighborhoods demographically different from their own. Nonetheless, restaurant consumption in New York City is only about half as segregated as residences. Consumption segregation owes more to social than spatial frictions.
What determines the distributions of skills, occupations, and industries across cities? We develop a theory that incorporates a system of cities, their internal urban structures, and a high-dimensional theory of factor-driven comparative advantage. It predicts that larger cities will be skill-abundant and specialize in skill-intensive activities according to the monotone likelihood ratio property. Data on US cities, education groups, occupations, and industries are consistent with our theory's predictions.
This paper shows that greater global spatial correlation of productivities can increase cross-country welfare dispersion by increasing the correlation between a country's productivity and its gains from trade. We causally validate this general-equilibrium prediction using a global climatic phenomenon as a natural experiment. We find that gains from trade in cereals over the last half-century were larger for more productive countries and smaller for less productive countries when cereal productivity was more spatially correlated. Incorporating this general-equilibrium effect into a projection of climate-change impacts raises projected international inequality, with higher welfare losses across most of Africa.
In developed economies, agglomeration is skill-biased. We construct metropolitan areas for Brazil, China, and India by aggregating finer geographic units on the basis of contiguous areas of light in nighttime satellite images. These lights-based metropolitan areas mirror commuting-based definitions in the US and Brazil. In China and India, lights-based metropolitan populations follow a power law, while administrative units do not. Examining variation in relative quantities and prices of skill across these metropolitan areas, we conclude that agglomeration is also skill-biased in Brazil, China, and India.
This course studies international economics from the perspective of the firm. Its objective is to equip students with analytical tools to understand the organizational, financial, and legal issues facing firms doing business across borders.