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...

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...

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...

Much of the political economy analysis of reform focuses on the conflict of interest between groups that stand to gain or lose from the competing policy proposals. In reality, there is also a lot of disagreement about the working of the policy: in addition to conflicting interests, conflicting...

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...

This paper discusses the specificities of the labor market for older workers. It discusses the implications of those specificities for the effect of labor market institutions on the employability of those workers. It shows that while unemployment benefits indexed backwards and hiring costs are...

This paper analyzes empirically the relationship between civil wars and international trade. We first show that trade destruction due to civil wars is very large and persistent and increases with the severity of the conflict. We then test the presence of two effects that trade can have on the...

This paper analyses theoretically and empirically the relationship between trade and war. We show that the intuition that trade promotes peace is only partially true even in a model where trade is beneficial to all, war reduces trade and leaders take into account the costs of war. When war can...

In this Paper, I analyse the pros and cons of implementing structural reforms of the labour market in booms versus recessions, in light of considerations of social efficiency, political viability, and macroeconomic fine-tuning. While the optimal timing of a reform depends on the relative...

This paper derives the conditions under which fitness-reducing alleles can survive in a long-run stationary equilibrium for a trading population, extending the results in Saint-Paul (2002) for arbitrary systems of sexual reproduction.