We examine aggregate productivity differences across nations using cross-country firm-level data and a quantitative model of production heterogeneity with distortions featuring operation decisions (selection) and productivity-enhancing investments (technology). Empirically, less developed...

"We develop a quantitative theory of human capital with heterogeneous agents in order to assess the sources of cross-country income differences. The cross-sectional implications of the theory and U.S. data are used to restrict the parameters of human capital technology. We then assess the...