The authors study the link between export product variety and country productivity based on data from 34 industrial and developing countries, from 1982 to 1997. They measure export product variety by the share of U.S. imports on the set of goods exported by each sampled country relative to the...

This paper provides evidence on the monopolistic competition model with heterogeneous firms and endogenous productivity. We show that this model has a well-defined GDP function where relative export variety enters positively, and estimate this function over 48 countries from 1980 to 2000....