Research

The transport sector is the backbone of international trade and has faced multiple disruptions in recent years. This paper studies how substitution across transport modes shapes international trade, welfare, and carbon emissions. Motivated by recent disruptions to air and maritime transport, I develop a quantitative multicountry trade model with multiple transport modes and endogenous congestion costs. I estimate the elasticity of substitution between transport modes at the country-pair level using the closure of Russian airspace as a quasi-natural experiment. I find an average elasticity of substitution between air and sea transport of 2.6. Counterfactual simulations show that allowing for mode substitution attenuates welfare losses from mode-specific transport shocks. However, since transport modes differ in carbon intensity, substitution also affects the environmental impact of trade and can weaken the effectiveness of environmental policies.
Presented at: ETSG, UEA European Meeting, GEP-CEPR Postgrad Conference, RIEF, EAYE, SETC, CEP/Warwick Junior Trade Workshop, Napoli Parthenope, Midwest Trade Conference, Norwegian School of Economics, World Bank Annual Conference on Transport Economics 2025.

We study how the interplay between oligopoly in the transportation industry and oligopsony power retained by non-atomistic importers affects the transmission of trade policy. Using Chilean customs data, we document strong concentration among carriers and importers and show that freight prices are determined through bilateral bargaining under two-sided market power. We estimate a trade model that endogenizes transportation costs by embedding oligopoly and oligopsony in the transport sector, along with bilateral bargaining. We find sizable carrier markups, partially offset by importer bargaining power. Embedding this mechanism into a quantitative trade model, we find that the endogenous response of transportation costs reduces the welfare cost of tariffs by 50% compared to the standard case of iceberg trade costs. This effect is primarily driven by decreasing returns to scale in carriers’ supply. Bargaining, in turn, plays a central role in shaping price levels and market allocations in the transportation sector.
Awards: Young Economist Award at 17th FIW International Economics Conference

The environmental impact of agricultural Global Value Chains (GVCs) has become an increasing source of concern. These chains are dominated by large international buyers whose sourcing strategies, shaped by managerial decisions, vary considerably. This paper investigates how such differences in sourcing organization relate to environmental outcomes within agricultural GVCs. Drawing on detailed transaction-level data from Côte d'Ivoire’s cocoa GVC, we find that buyers adopting more relational sourcing strategies are associated with lower levels of deforestation. This effect is mediated by managers’ educational backgrounds which influence the sourcing strategies their firms adopt and, ultimately, deforestation. Overall, the findings highlight the central role of buyer–supplier relationships in either promoting or constraining environmental sustainability in agricultural GVCs.

This paper studies how international buyers’ market power and transport mode shape the pass-through of exchange rate shocks to export prices. Using transaction-level customs data from the Bangladeshi garment sector, we first document substantial buyer market power and the concentration of export activity in key trade hubs that shape transport decisions. We then show that large buyers leverage both their market power and their reliance on air freight to mitigate the impact of exchange rate fluctuations. Taken together, our findings highlight how buyer characteristics shape exporters’ adjustment to external shocks, with broader implications for regional economic resilience.

Brexit is a striking example of a potentially new era of trade disintegration. We estimate its effect on UK-EU goods trade using monthly bilateral trade data for 50 countries at the HS2 product level. Under various de-trending approaches, we find that the shift from EU membership arrangements to the Trade and Cooperation Agreement (TCA) in January 2021 caused a 17–18% fall in UK-EU trade. However, the longer-run effect, comparing pre-referendum with post-TCA trade, is sensitive to how trends are included, as estimates for the interim period between the referendum and Brexit vary substantially by trend choice. By product type, TCA implementation mainly reduced trade in consumer and intermediate goods, with no significant effect on capital goods. Further, we find no clear correlation between the trade effects and the goods-level trade elasticities reported by Fontagné et al. (2022).