Research

We examine how diversification in import sourcing moderates resilience to upstream shocks, focusing on two specific but recurrent risks: pandemics and geopolitical conflicts. Using annual data on global trade and weekly data from Swiss importing firms, we assess how diversification before an upstream shock affects the growth rate of imports at the product level.

Guided by a theoretical framework that introduces risk aversion into global sourcing, we estimate a reduced-form gravity model and report two sets of empirical findings. First, we establish that both shocks significantly reduce the growth rate of imports. Second, using various diversification measures defined at the importer-product level, we show that more diversified firms exhibit greater resilience to these disruptions — importers with higher pre-shock source diversity show lower declines in import growth during a shock. That the results align across macro and micro levels enhances the external validity of our findings.

Risks are inherent and increasingly recognized in global agricultural value chains; however, their effects and firm-level responses are poorly understood. Using novel global firm-to-firm trade data, we show that agricultural markets are highly concentrated and have sparse network structures, with buyers typically relying on a limited set of suppliers, and prices are shaped by the two-sided market power of both importers and exporters.

We find that U.S. import prices are lower when importers account for a larger share of purchases, and that price volatility is reduced when firms diversify their foreign suppliers, for example in response to the Ukraine-Russia war. Motivated by these findings, we develop the first structural model of international sourcing under matching frictions and risk aversion applied to agricultural markets. Firms adjust along three margins: absorbing shocks, renegotiating with existing suppliers, or diversifying by switching to new suppliers. Our counterfactual exercises show that policies promoting import-source diversification and reducing matching frictions enable importers to access new suppliers and help stabilize agricultural prices.

We investigate whether EU border rejections of food and agricultural products are driven primarily by food safety concerns or by political and trade-policy considerations. Using machine learning methods, we build a predictive model of rejection risk and decompose the relative importance of safety, regulatory, and geopolitical factors across product-origin pairs.

Global food price crises recur with increasing frequency, yet their political consequences remain contested. We examine how exposure to global commodity price shocks shapes state fragility across 170 countries from 2007 to 2023 using predetermined country-level commodity exposure shares to construct exogenous, country-specific price shock measures. Our design allows to test the theoretical mechanisms that determine stabilizing or destabilizing effects of food price movements and estimate their relative effects. Our results suggest that producer-side effects dominate globally where food price rises reduce fragility through opportunity cost and state capacity channels, driven by large producer shares in low and middle income countries. In high income countries, price rises in animal products increase fragility via relative deprivation. This pattern has growing relevance as structural transformation shifts populations from food producers to net consumers.

We study how geopolitical risk — measured through both index-based approaches and event studies — transmits into agricultural commodity prices. The project combines structural time-series methods with high-frequency market data to identify the channels through which political uncertainty reaches food markets.

We estimate the effect of minimum wage regulations on agricultural export competitiveness and trade flows, exploiting cross-country and cross-sector variation in minimum wage levels and changes.