New empirical and theoretical work has highlighted the importance of multi-product firms in international tradeflows. We examine multi-product exporters in the small open economy of Belgium, considering their importance and the relationship between the margins of trade and firm productivity,...

This paper quantifies the origins of firm size heterogeneity when firms are interconnected in a production network. Using the universe of buyer-supplier relationships in Belgium, the paper develops a set of stylized facts that motivate a model in which firms buy inputs from upstream suppliers...

This paper develops a general equilibrium model of international trade that features selection across firms, products and countries. Firms' export decisions depend on a combination of firm “productivity” and firm-product-country “consumer tastes,' both of which are stochastic and unknown...