Publications:

Evolving Comparative Advantage and the Impact of Climate Change in Agricultural Markets: Evidence from 1.7 Million Fields around the World (with Arnaud Costinot and Dave Donaldson), Journal of Political Economy, 124(1), February 2016: 205-248

Abstract: A large agronomic literature models the implications of climate change for a variety of crops and locations around the world. The goal of the present paper is to quantify the macro-level consequences of these micro-level shocks. Using an extremely rich micro-level data set that contains information about the productivity—both before and after climate change—of each of 10 crops for each of 1.7 million fields covering the surface of the earth, we find that the impact of climate change on these agricultural markets would amount to a 0.26 percent reduction in global GDP when trade and production patterns are allowed to adjust. Since the value of output in our 10 crops is equal to 1.8 percent of world GDP, this corresponds to about one-sixth of total crop value.

Coverage: Washington Post, MIT News

Working Papers:

When is Long-run Agglomeration Possible? Evidence from County Seat Wars (with Amrita Kulka)

Abstract: We study the factors that foster long-run urban growth using a unique setting of close elections that determined “county seats” (capitals) in the frontier United States. Using a regression discontinuity design, we show that winning towns experienced rapid population and income growth as migrants coordinated on them as their counties' economic centers. We show that this coordination was largest in smaller towns and in the years close to county creation. Using generalized random forests, we also show that the economic benefits were not zero sum locally: specific choices of county seat could increase long-run county population and income. County administration was limited in this era and did not play a substantial role in this process. Instead, these results are consistent with theories of economic geography in which there are strong local returns to scale and equilibria can be selected through historical and political events, even when geographic fundamentals are similar.

Land Concentration and Long-Run Development in the Frontier United States

Conditionally Accepted: American Economic Journal: Applied

Abstract: I study the long-run economic effects of land concentration on the American frontier. Using quasi-random variation in initial land allocations from a checkerboard formula, I analyze a database of property assessments covering over 380,000 square miles and find that historical concentration reduced modern land values by 4.5%, fixed capital by 23%, and population by 9.1%. These effects are 23%-64% the size of their historical equivalents, indicating significant rates of both persistence and convergence in the last 150 years. Data from archival surveys reveal that initial land concentration increased landowners' reliance on tenant farmers for over a century, and counties with high rates of share tenancy experienced the largest negative effects on land value. These findings suggest that share tenancy's contracting inefficiencies discouraged large-scale owners from land investment, with long-term economic consequences.

Coverage: VoxDev

When Coercive Economies Fail: The Political Economy of the US South After the Boll Weevil (with James Feigenbaum and Soumyajit Mazumder)

Abstract: How do coercive societies respond to negative economic shocks? We explore this question in the early 20th century United States South. Since before the nation's founding, cotton cultivation formed the politics and institutions in the South, including the development of slavery, the lack of democratic institutions, and intergroup relations between whites and blacks. We leverage the natural experiment generated by the boll weevil infestation from 1892-1922, which disrupted cotton production in the region. Panel difference-in-differences results provide evidence that Southern society became less violent and repressive in response to this shock with fewer lynchings and less Confederate monument construction. Cross-sectional results exploiting spatial variation in the infestation and historical cotton specialization show that affected counties had less KKK activity, higher non-white voter registration, and were less likely to experience contentious politics in the form of protests during the 1960s. To assess mechanisms, we show that the reductions in coercion were responses to African American out-migration. Even in a context of coercive and antidemocratic institutions, ordinary people can retain political power through the ability to “vote with their feet.”

Works in Progress:

Is Basic Democracy Enough?

In many contexts, elections only partially determine political authority. I examine the impacts of increasing electoral representation in Pakistan's 1960s local councils known as the “Basic Democracies.” Councilors could either be popularly elected or directly appointed by the military-led government. A formulaic quirk in the establishing law caused their relative proportion of elected members to vary in an alternating pattern as a function of council size. I use this pattern to identify the causal effects of electoral representation on councils’ public goods provision, taxation initiatives, and the subsequent impacts on long-run growth. I examine mechanisms including politician selection and cooperation, alignment with the central government, and manipulation of council structure. The analyses can inform our understanding of when elections are effective, particularly in so-called hybrid systems that mix democratic and nondemocratic elements.