The theoretical debate over whether countries can and should set tariffs in response to the foreign export elasticities they face goes back to Edgeworth (1894). Despite the centrality of the optimal tariff argument in trade policy, there exists no evidence about whether countries actually...

Since the seminal work of Krugman (1979), product variety has played a central role in models of trade and growth. In spite of the general use of love-of-variety models, there has been no systematic study of how the import of new varieties has contributed to national welfare gains in the United...

"The empirical literature in international finance has produced three key results about international price deviations: borders give rise to flagrant violations of the law of one price, distance matters enormously for understanding these deviations, and most papers find that convergence rates...