-product firms live forever, and the large firms invest in innovation in order to enlarge their product spans. All firms export. I …

We study unanticipated tariffs on imports of intermediate goods in a setting with firm-to-firm supply relationships … free trade. Once they are in place, the home government surprises with an input tariff. This can lead to renegotiation with … deterioration in the terms of trade. The welfare implications of a tariff are ambiguous in this second-best setting, but plausible …

aggregate export and FDI sales relative to the domestic and foreign market sizes. In particular, it is shown that firm level … heterogeneity is an important determinant of relative export and FDI flows. We use the model to derive testable empirical … predictions on the relative aggregate export and FDI sales in a given country for a given sector based both on relative costs and …

unions to estimate the effect of currency unions on trade using (then-) conventional gravity models. In this paper, we use a … variety of empirical gravity models to estimate the currency union effect on trade and exports, using recent data which … a smaller trade effect than other currency unions; it has a mildly stimulating effect at best. Third and most …