empirical studies have largely focused on measuring the gains from an increased variety of imports. Trade theory, however …

international trade flows, and the well-known - and traditionally presumed exogenous - "trade-cost elasticity" plays a central role …-cost elasticity. We offer four potential contributions. First, for motivation, we show empirically that the heterogeneity in various …

importers. This theory is guided by new findings drawn from a matched exporter-importer dataset that characterizes the … features simultaneous free entry into exporting and into importing. This theory provides a rationale for the fixed costs of … trade flows across sectors and destinations. I test this theory by studying the response of exporting and importing firms to …