How shifts in the economic leadership between countries can occur has been widely debated not only since the recent catch up of China in several sectors. However, there is no adequate theoretical model analyzing this question in the light of trade liberalization. This paper is the first one to...

This paper sets up a heterogeneous firms model, where production consists of a continuum of tasks that differ in complexity. Firms hire low-skilled and high-skilled workers to perform these tasks. How firms assign workers to tasks depends on factor prices for the two skill types and the...

We derive a simple equation for the welfare gains from trade when tariffs are liberalized or iceberg trade costs fall. Covering various one-sector trade models that may or may not feature extensive margins and imperfect competition, we generalize the analysis of Arkolakis, Costinot and...