Trade costs are often additive. Well-known examples are quotas, per unit tariffs, and, in part, transportation costs. In spite of this, we have no broad and systematic evidence of the magnitude of these costs. In this paper, we develop a new empirical framework for estimating additive trade costs from standard firm-level trade data. Our results suggest that additive barriers are on average 14%, expressed relative to the median price. The point estimates are strongly correlated with common proxies for trade costs. Using our microestimates, we show that an additive import tariff reduces welfare and trade by more than an equal-yield multiplicative tariff.

Multinational production (MP) can lead to large gains through international technology sharing. However, empirical evidence suggests that geography matters for MP: Affiliate sales fall in distance from the headquarters. We introduce intrafirm trade into a standard model of exports and MP and show that the model is consistent with firm-level and aggregate evidence. Using a maximum likelihood estimator, we find that intrafirm trade plays a crucial role in shaping the geography of MP. An implication of our work is that MP and exports are very similar activities. Consequently, shutting down MP leads to relatively small welfare losses.

We investigate how managers help firms grow by entering a new export market. We conduct an event study on the decision to export to Angola using data on Portuguese firms and workers. We evaluate the impact of the presence of managers with experience in exporting to the Angolan market on a firm’s entry success in the aftermath of an exogenous shock: the sudden end of the Angolan civil war. We show that the presence of managers doubles the probability of a firm entering the market. We do not find any significant impact on the intensive margin of exports.

We build a multicountry dynamic general equilibrium model to study the economic effects of the 2004 enlargement of the European Union. In our model, trade is costly and households of different skills and nationalities face costly forward-looking migration decisions. We exploit the timing of migration policy changes to identify the changes in migration costs. We find that the changes in migration and trade policy resulted in aggregate welfare gains but with heterogeneous effects across skill groups. We study the interaction between trade and migration policies and highlight the importance of trade for quantifying the welfare and migration effects of labor market integration.

Using employer-employee matched and firm production quantity and input data for Portuguese firms, we study the endogenous response of productivity to firm reorganizations as measured by changes in the number of management layers. We show that, as a result of an exogenous demand or productivity shock that makes the firm reorganize and add a management layer, quantity-based productivity increases by about 6%, while revenue-based productivity drops by around 3%. Such a reorganization makes the firm more productive but also increases the quantity produced to an extent that lowers the price charged by the firm and, as a result, its revenue-based productivity as well.