Is the variation in bilateral trade flows across countries primarily due to differences in the number of exporting firms (the extensive margin) or in the average size of an exporter (the intensive margin)? And how does this affect the estimation and quantitative implications of the Melitz (2003)...

The Melitz model highlights the importance of the extensive margin (the number of firms exporting) for trade flows. Using the World Bank's Exporter Dynamics Database (EDD) featuring firm-level exports from 50 countries, we find that around 50 percent of variation in exports is along the...

We examine how deep agreements on domestic regulations affect welfare in a world where such agreements are influenced by producer lobbies. The answer to this question depends in a critical way on whether the agreement focuses on product standards or on production regulations. International...

Over the WTO years, the frequency of disputes and court rulings has trended downwards. Such trends are sometimes interpreted as symptoms of a dispute resolution system in decline. In this paper we propose a theory that can explain these trends as a result of judicial learning; thus according to...

Over the WTO years, the frequency of disputes and court rulings has trended downwards. Such trends are sometimes interpreted as symptoms of a dispute resolution system in decline. In this paper we propose a theory that can explain these trends as a result of judicial learning; thus according to...

We examine how deep agreements on domestic regulations affect welfare in a world where such agreements are influenced by producer lobbies. The answer to this question depends in a critical way on whether the agreement focuses on product standards or on production regulations. International...