International market segmentation and globalization in open macroeconomics.

Summary Numerous studies highlight the existence of substantial costs affecting international trade flows. By creating a segmentation of international markets, these trade barriers affect the global equilibrium in open macroeconomics. However, most macroeconomic models ignore this feature of the international economy and assume perfect market integration. The three parts that make up this thesis study the impact of this segmentation of international markets on macroeconomic equilibrium. The tools developed by the New Trade Theories are used to model the impact of trade barriers on the strategic decisions of firms in a globalized environment. The first part of the thesis focuses on the consequences of market segmentation on export pricing strategies. The empirical analysis highlights the microeconomic determinants that explain the low sensitivity of trade prices to exchange rate fluctuations. The second part introduces the analysis of firms' location choices and studies their impact on the level of relative prices. It shows how the entry of new producers into a national market exerts downward pressure on its aggregate price level. Finally, the third part of the thesis examines the impact of these location choices on the efficiency of economic policies. More precisely, it shows how national minimum wage policies affect the spatial distribution of firms, through the relative costs of production but also through their impact on aggregate demand.