Proper measurement and aggregation of trade costs is of paramount importance for sound academic and policy analysis of the determinants - particularly those of policy - of economic outcomes. The international trade profession has witnessed significant new developments, both on the theoretical...

We set up a trade model with heterogeneous firms and a worker population that is heterogeneous in two dimensions: workers are either skilled or unskilled, and within each skill category there is a continuum of abilities. Workers with high abilities, both skilled and unskilled, are matched to...