Ricardo's Theory of Comparative Advantage: Old Idea, New Evidence
---- Acknowledgements -----
We thank Pol Antràs, Chang-Tai Hsieh, and Esteban Rossi-Hansberg for comments and Meredith McPhail and Cory Smith for excellent research assistance. This paper has been prepared for the 2012 American Economic Review Papers and Proceedings. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.