Information sets, expectations, and preferences of politicians are fundamental, but unobserved determinants of their policy choices. Employing repeated votes in the US House of Representatives on China’s normal trade relations (NTR) status during the two decades straddling China’s World Trade Organization (WTO) accession, we apply a moment inequality approach designed to deliver consistent estimates under weak informational assumptions on the information sets of members of Congress. This methodology offers a robust way to test hypotheses about what information politicians have at the time of their decision and to estimate the weight that constituents, ideology, and other factors have in policy making and voting.

Is skill dispersion a source of comparative advantage? In this paper we use microdata from the International Adult Literacy Survey to show that the effect of skill dispersion on trade flows is quantitatively similar to that of the aggregate endowment of human capital. In particular we investigate, and find support for, the hypothesis that countries with a more dispersed skill distribution specialize in industries characterized by lower complementarity of workers' skills. The result is robust to the introduction of controls for alternative sources of comparative advantage, as well as to alternative measures of industry-level skill complementarity.