This chapter focuses on the estimation and interpretation of gravity equations for bilateral trade. This necessarily involves a careful consideration of the theoretical underpinnings since it has become clear that naive approaches to estimation lead to biased and frequently misinterpreted...

Investigations of the effect of quality differences on heterogeneous performance in exporting have been limited by lack of direct measures of quality. We examine exports of French wine, matching the exporting firms to producer ratings from two wine guides. We show that high quality producers...

With increasing sophistication, economists have been estimating gravity equations for five decades. Robust evidence shows that borders and distance impede trade by much more than tariffs or transports costs can explain. We therefore advocate investigation of other sources of resistance, despite...

Quantifications of gains from trade in heterogeneous firm models assume that productivity is Pareto distributed. Replacing this assumption with log-normal heterogeneity retains some useful Pareto features, while providing a substantially better fit to sales distributions—especially in the left...