This lecture continues with empirical estimation of firm productivity using firm level data. It proceeds to discuss trade policy and development. It studies welfare implications of trade policy tools such as tariffs, quotas, anti-dumping duties and export subsidies.

This lecture continues to explore "New Trade Theory" with the Melitz model of heterogeneous firms. It then switches to estimation of the gravity model of trade using cross-country data and talks about potential solutions to tackle empirical challenges associated with estimation.

This lecture begins with a discussion of the Heckscher-Ohlin (HO) model of trade. Within the HO framework, it explores issues related to trade and inequality and the impact of immigration on the domestic economy. It ends with an introduction to "New Trade Theory", beginning with Krugman's model of trade under monopolistic competition.

This lecture introduces the concept of comparative advantage as a driver of international trade and discusses neo-classical models of trade, starting with the Ricardian model.