Increasing-returns-to-scale imperfect competition trade models predict a more than proportionate relationship between the larger country's share in world endowments and its share in producing firms: the so called home market effect (HME). While this result plays a key role in empirical testing,...

Increasing-returns-to-scale imperfect competition trade models predict a more than proportionate relationship between the larger country's share in world endowments and its share in producing firms: the so called home market effect (HME). While this result plays a key role in empirical testing,...

In the two-country Melitz (2003) model, unilateral trade liberalization is often cast as a reduction of iceberg transportation costs and wages are determined by a linear outside sector. We show that welfare results reverse when wages adjust and trade frictions are revenue-generating tariffs. --...

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...