Publications

We study rainmaking as an instrumental religious belief. We present a model in which a religious leader tries to persuade people to believe. Praying for rain can persuade only where the hazard of rainfall during a dry spell is increasing over time, so that prayer is most likely to succeed when people most want rain. We present evidence from prayers for rain in Murcia, Spain, where the hazard rate is increasing, that the church’s prayers for rain predict rainfall over two centuries. To generalize this finding, we gather an original data set of whether ethnic groups around the world traditionally prayed for rain. We find that ethnic groups facing an increasing rainfall hazard are 47% more likely to pray for rain, consistent with our model’s prediction that societies are more likely to pray for rain where prayer is persuasive.

Do elite colleges help talented students join the social elite or help incumbent elites retain their positions? We combine intergenerationally linked data from Chile with a regression discontinuity design to show that, looking across generations, elite colleges do both. Lower-status individuals who gain admission to elite college programs transform their children's social environment. Children become more likely to attend high-status private schools and colleges and to live near and befriend high-status peers. In contrast, academic achievement is unaffected. Simulations combining descriptive and quasi-experimental findings show that elite colleges tighten the link between social and human capital while decreasing intergenerational social mobility.

We study the optimal design of trade and industrial policy when governments pursue environmental objectives alongside traditional national welfare. Motivated by the global transition to electric vehicles (EVs) and growing concerns about competitiveness, resilience, and the environment, we develop a framework in which policymakers choose tariffs and domestic production subsidies to maximize national welfare, defined as the sum of consumer surplus, domestic profits, environmental benefits, and tariff revenue net of subsidies. We combine a theoretical model of differentiated-product oligopoly with a structural demand model estimated using vehicle-level data from 13 countries during 2004-2023 that together account for the vast majority of global EV sales. Our central finding is that the optimal policy combines a moderate tariff on imported EVs with a subsidy to domestic EV production financed through tariff revenue. This policy substantially outperforms both outright protectionism and laissez-faire. Relative to current policies, it preserves consumer access to affordable EVs, accelerates fleet electrification, supports domestic producers, and remains budget-neutral. For the United States, the optimal policy more than doubles EV market share, generates over $45 billion in annual welfare gains, and avoids approximately 95 million tons of lifetime CO2 emissions. A key mechanism underlying these results is the pass-through of tariffs and subsidies to prices, which depends critically on demand curvature, product substitution, and market structure. More broadly, our results suggest that effective industrial policy requires careful attention to market structure and country-specific conditions, balancing consumer, producer, fiscal, and environmental objectives rather than adhering to ideological prescriptions.

This paper studies how the risk of hold-up affects procurement. I use data on the universe of solar power auctions in India. The Indian context allows clean estimates of counterparty risk, because solar plants set up in the same states, by the same firms, are procured in auctions intermediated by either risky states themselves or the trusted central government. I find that the counterparty risk of an average state increases solar prices by 10%. This risk premium sharply reduces investment, because demand for green energy is elastic. Contract intermediation by the central government eliminates the counterparty risk premium.

This article studies the effects of automation in a task-based economy in which some jobs pay workers rents—wages above workers' outside options. We show that automation targets high-rent tasks, dissipating rents, amplifying wage losses, and reducing within-group wage dispersion in exposed groups. This form of rent dissipation is inefficient and offsets the productivity gains from automation. Using U.S. data from 1980 to 2016, we find evidence of sizable rent dissipation and reduced within-group wage dispersion due to automation. Automation accounts for 52% of the increase in between-group inequality since 1980, with rent dissipation explaining one-fifth of this total. Our estimates imply that inefficient rent dissipation has offset 60%–90% of the productivity gains from automation over this period.

We document employment preferences of workers at the margin of informality using open-ended questions and discrete choice experiments in Brazil's largest favela complex. Stated preferences emphasize pay and tangible job attributes rather than meaning or purpose. Stated complaints center on management, customers, and inflexible schedules. Workers exhibit high willingness to pay for unemployment insurance, parental leave, and learning opportunities, but none for termination notice or shorter commutes. We find larger willingness to accept to forgo amenities than willingness to pay to obtain them, consistent with preference-based sorting or endowment effects.

We study the large-scale experimental rollout of a platform that reduced search and matchingfrictions in Ugandan agricultural markets by connecting buyers and sellers. Market integrationimproved substantially: trade increased and price gaps fell. Interpreting the experiment througha trade model, we estimate treatment effects accounting for equilibrium changes that impactcontrol markets. The intervention reduced fixed trade costs by 20% and increased trade flowsbetween treated markets by 7% and across all markets by 1%. Scale economies shaped engagement:few farmers used the platform, but equilibrium price convergence from improved arbitrage bylarger traders passed through to farm revenue.

We examine the effects of international trade in the presence of a set of domestic distortions giving rise to informality, a prevalent phenomenon in developing countries. In our quantitative model, the informal sector arises from burdensome taxes and regulations that are imperfectly enforced by the government. In equilibrium, smaller, less productive firms face fewer distortions than larger, more productive ones, potentially leading to substantial misallocation. We show that in settings with a large informal sector, the gains from trade are significantly amplified, as reductions in trade barriers imply a reallocation of resources from initially less distorted to more distorted firms. We confirm findings from earlier reduced‐form studies that the informal sector mitigates the impact of negative labor demand shocks on unemployment. Nonetheless, the informal sector can exacerbate the adverse real income effects of economic downturns, amplifying misallocation. Last, our research sheds light on the relationship between trade openness and cross‐firm wage inequality.

Since the late 1980s, extreme poverty has declined sharply, life expectancy and schooling have increased, and electoral democracy has expanded. However poverty reduction has slowed in recent years, particularly following the COVID-19 pandemic, amid intensifying conflict, fragility, climate risks, democratic backsliding, and the erosion of global trends—including trade integration and geopolitical stability—that once supported growth. These dynamics raise three interrelated questions: what barriers impede further progress; where will future growth in lower-income countries come from; and how can growth be broadly shared. Taking stock of 15 chapters forthcoming in Volume 6 of the Handbook of Development Economics, we discuss how external conditions, state capacity and policy choices shape development; analyze the shifting growth drivers, including trade, technology and the rise of services; discuss persistent inequality and distributional tensions; and conjecture that investing in institutions and people pays off.

We analyze a nonlinear pricing model where the seller controls both product pricing (screening) and buyer information about their own values (persuasion). We prove that the optimal mechanism always consists of finitely many signals and items, even with a continuum of buyer values. The seller optimally pools buyer values and reduces product variety to minimize informational rents. We show that value pooling is optimal even for finite value distributions if their entropy exceeds a critical threshold. We also provide sufficient conditions under which the optimal menu restricts offering to a single item.

We investigate the efficiency of a market relative to a non-market institution—an auction relative to a quota—as allocation mechanisms in the presence of frictions. We use data from water markets in southeastern Spain and explore a specific change in the institutions to allocate water. On the one hand, frictions arose because poor farmers were liquidity constrained. On the other hand, farmers who were part of the wealthy elite were not liquidity constrained. We estimate a structural dynamic demand model by taking advantage of the fact that water demand for both types of farmers is determined by the technological constraint imposed by the crop’s production function. This approach allows us to differentiate liquidity constraints from unobserved heterogeneity. We show that the institutional change from an auction to a quota increased total efficiency for the farmers considered. Welfare increased by 23.4 real pesetas per farmer per tree, a 6 % increase in total production relative to the market.

During adolescence, peer interactions become increasingly central to children’s development, whereas the direct influence of parents wanes. Nevertheless, parents can continue to exert leverage by shaping their children’s peer groups. We construct and estimate a model of parenting with peer and neighborhood effects where parents intervene in peer formation and show that the model captures empirical patterns of skill accumulation, parenting style, and peer characteristics among US high school students. We find that interventions that move children to better neighborhoods lose impact when they are scaled up, because parents’ equilibrium responses push against successful integration with the new peer group.

Economic development relies on and transforms the environment. The transformation is evident in the poor environmental quality in many developing countries. For example, air quality in Southeast Asia is three times worse than in the United States, in sub-Saharan Africa four times worse and in South Asia more than six times worse. We model how environmental quality affects health, productivity and well-being and how individuals privately adapt to environmental hazards. We also model how collective action and formal regulation contribute to environmental quality. We draw three main findings from a review of empirical research on these mechanisms. First, individual adaptation to environmental hazards is both inadequate as a remedy and inefficiently low. Second, collective action, without the state, to manage resources or address externalities has been outstripped by the scale of environmental problems. Third, state action through formal regulation works better than it looks. Many formal regulations are coarse, poorly targeted and inefficient, but nonetheless yield benefits in excess of their costs.

This chapter takes stock of what has been learned from the recent micro-development literature about wedges—mechanisms generating dispersion in marginal revenue products of factors across firms, which are commonly interpreted as indicators of misallocation. We present a general theoretical framework that allows us to consider several different types of wedges simultaneously. We argue that it is important to distinguish between between technological wedges, which are present even in the efficient allocation that would be chosen by the social planner, and distortionary wedges, which are present in market equilibrium but not the social planner's allocation. Not all wedges, as we have defined them, are distortionary. We also argue that interactions among wedges are pervasive. We review empirical findings about different types of wedges—taxes, regulations, political connections, corruption, market power, contracting frictions, upgrading investments, and search—focusing on studies that present direct evidence on particular wedges and how they generate dispersion in marginal returns to factors. Throughout, we pay special attention to how wedges vary with firm size and whether the evidence supports the “large firms are constrained” view of development. We conclude with thoughts about promising directions for the misallocation literature.

In today’s developing world, many economies appear to bypass industrialization and transition directly from agriculture to services. The largest rise in service employment has occurred in non-tradable consumer services, such as retail and hospitality, especially in urban areas, where many cities resemble consumer hubs built around local demand. These patterns of growth raise fundamental questions: Can service-led growth sustain improvements in living standards over time? Is service-led growth inherently biased toward affluent urban consumers? What role should policy play? To address these questions, we propose a parsimonious general equilibrium framework that incorporates non-homothetic preferences and locally non-tradable consumer services in a spatial setting. We apply the framework to a set of fast-growing sub-Saharan African economies and contrast their experience with economies following more industrialization-led path, highlighting how service-led growth shapes productivity, welfare, and inequality. Our framework bridges macro and micro perspectives and enables counterfactual analysis that accounts for both individual and spatial heterogeneity. We relate the framework to the recent literature and discuss several extensions and directions for future research.