Firms play a critical role in the global economy. In this paper, we survey the behavior of firms in the international economy, both in theory and in the data. We first summarize the key empirical facts that motivate the study of firms in trade. Then, we detail recent theoretical developments on...

Global value chains have fundamentally transformed international trade and development in recent decades. We use matched firm-level customs and manufacturing survey data, together with Input-Output tables for China, to examine how Chinese firms position themselves in global production lines and...

Gravity equations have been used for more than 50 years to estimate ex post the partial effects of trade costs on international trade flows, and the well-known - and traditionally presumed exogenous - "trade-cost elasticity" plays a central role in computing general equilibrium trade-flow and...

We present a gravity model that accounts for multilateral resistance, firm heterogeneity and country-selection into trade, while accommodating asymmetries in trade flows. A new equation for the proportion of exporting firms takes a gravity form, such that the extensive margin is also affected by...

Was the collapse of world trade between 1928 and 1937 caused by higher transport costs, increased protectionism or the collapse of the gold standard? Using recent advances in the estimation of gravity equations, I examine the partial and general equilibrium effects of bilateral distance,...

Although economists have long been aware of Jensen's inequality, many econometric applications have neglected an important implication of it: estimating economic relationships in logarithms can lead to significant biases in the presence of heteroskedasticity. This paper explains why this problem...

The paper reviews selected implications of trade integration via global value chains (GVC) and identifies gaps in understanding of GVC risks. Despite recent significant progress, many GVC risks remain unknown. The paper also discusses pros and cons of possible strategies to minimise GVC risks...

We study how financial frictions affect firm-level heterogeneity and trade. We build a model where productivity differences across monopolistically competitive firms are endogenous and depend on investment decisions at the entry stage. By increasing entry costs, financial frictions lower the...

This paper aims to examine the changes in global value chains (GVCs) in the years 2020-2022 (times of the COVID-19 pandemic) compared to 2019 (last year before the pandemic). GVCs are illustrated by diagrams based on the statistics on international trade measured by value-added exports and...

As countries and firms increasingly seek ways to strengthen the resilience of their supply chains, this paper studies the global economic costs of a decoupling of global supply chains along geopolitical lines as well as in strategic sectors. We explore not only the long-run effects, but also the...