Publications

We consider a multiproduct seller who has access to information about consumer preferences that he can use for second- and third-degree price discrimination. We characterize markets for which such information can lead to the efficient allocation with consumers obtaining the entire surplus gain relative to the profit-maximizing allocation without the additional information. This benchmark is achievable for all markets with a given set of consumer types if and only if it is optimal for the seller to offer only the best product in each market. Analogous results characterize when the "surplus triangle" of Bergemann, Brooks, and Morris (2015) is achievable.

Airfares fluctuate due to demand shocks and intertemporal variation in willingness to pay. I estimate a model of dynamic airline pricing accounting for both sources of price adjustments using flight-level data. I use the model estimates to evaluate the welfare effects of dynamic airline pricing. Relative to uniform pricing, dynamic pricing benefits early-arriving, leisure consumers at the expense of late-arriving, business travelers. Although dynamic pricing ensures seat availability for business travelers, these consumers are then charged higher prices. When aggregated over markets, welfare is higher under dynamic pricing than under uniform pricing. The direction of the welfare effect at the market level depends on whether dynamic price adjustments are mainly driven by demand shocks or by changes in the overall demand elasticity.

This chapter reviews a recent body of theoretical and empirical work that studies the normative and positive aspects of trade policy. We start by presenting reduced-form evidence of the effects of trade policy in the presence of supply-chain linkages, on the short-run and persistent effects of trade policy across local labor markets, and on the effects of trade policy uncertainty on employment and firms. We describe the shift-share method for trade policy analysis, discuss the interpretation of the estimated effects, and provide a theoretical foundation. We then describe new quantitative frameworks, methods, and data used to study the aggregate and distributional effects of trade policy in general equilibrium. We discuss how to take into account supply-chain linkages, local labor markets, and different sources of dynamics. As an illustration, we quantify the aggregate and distributional effects of the 2018 trade war between the United States and its trading partners. Finally, we present recent theoretical insights on optimal unilateral trade policy with firm and product heterogeneity in the context of large and small open economies with perfectly and imperfectly competitive product markets. We also discuss how optimal trade policy is shaped by the presence of multiple sectors, intermediate goods, and supply-chain linkages. We close the chapter by discussing the scope of future research.

Across a broad range of equipment types and industries, we document a pattern of local capital reallocation from older firms to younger firms. Start-ups purchase a disproportionate share of old physical capital previously owned by more mature firms. The evidence is consistent with financial constraints driving differential demand for vintage capital. The local supply of used capital influences start-up entry, job creation, investment choices, and growth, particularly when capital is immobile. Meanwhile, as suppliers of used capital, incumbents accelerate capital replacement in the presence of younger firms. The evidence suggests previously undocumented benefits to co-location between old and young firms.

Sports betting markets offer a novel laboratory to test theories of cross-sectional asset pricing anomalies found in financial markets. Two unique features of this market – no systematic risk and terminal values exogenous to betting activity – evade the joint hypothesis problem that allows mispricing to be detected. Examining more than one hundred thousand liquid betting contracts spanning three decades across four professional sports, I find strong evidence of momentum and weak evidence of value effects that are consistent with a model of delayed overreaction and reject models of underreaction and rational pricing. The magnitudes of momentum and value returns are a fraction of those in financial markets, and fail to overcome transactions costs, which prevents arbitrage from eliminating them. A novel insight from sports betting also predicts value and momentum returns in U.S. equities