This paper analyzes international externalities of a local shock to the global shipping network. The 2016 Panama Canal expansion removed a bottleneck in seaborne transportation. Using reduced-form and structural methods in combination with novel satellite data on ships, we find that trade increased significantly among country-pairs using the canal. We find that the global real income gains from the canal expansion were over three times greater than the income gains for Panama itself. A link removal analysis reveals that most shipping links are associated with positive and quantitatively important positive international externalities.

This paper estimates the effect on innovation of increased market access facilitated by trade liberalization. We use a novel empirical design that exploits tariff cuts during the 1990s, along with detailed data on innovation among firms from 65 countries. Our results reveal a large effect of tariff cuts on innovation as measured by patent data, suggesting that multilateral liberalization has promoted innovation and growth. These effects are not driven by the deterioration of innovation quality, and the results are robust to controlling for changes in the patent system and to industry-wide trends in innovation.

This paper develops a multicountry model of international trade that provides a simple microfoundation for buyer-seller relationships in trade. We explore a rich data set that identifies buyers and sellers in trade and establish a set of basic facts that guide the development of the theoretical model. We use predictions of the model to examine the role of buyer heterogeneity in a market for firm-level adjustments to trade shocks, as well as to quantitatively evaluate how firms’ marginal costs depend on access to suppliers in foreign markets.

We investigate to what extent worker heterogeneity explains the well-known wage and productivity exporter premiums, employing a matched employer-employee data set for Norwegian manufacturing. The wage premium falls by roughly 50% after controlling for observed and unobserved worker characteristics, while the total factor productivity premium falls by 25% to 40%, suggesting that sorting explains up to half of these premiums. Recent trade models emphasize the role of within-industry reallocation of labor in response to various shocks to the economy. Our findings suggest that aggregate productivity gains due to reallocation may be overstated if not controlling for sorting between firms and workers.