The Margins of Global Sourcing: Theory and Evidence from US Firms
构建了一个可量化的多国采购模型，企业根据生产率和国家特定变量自我选择是否进口，发现不同来源市场的采购决策存在互补性，这种相互依赖影响企业对贸易冲击的国内采购反应。
We develop a quantifiable multi-country sourcing model in which firms self-select into importing based on their productivity and country-specific variables. In contrast to canonical export models where firm profits are additively separable across destination markets, global sourcing decisions naturally interact through the firm's cost function. We show that, under an empirically relevant condition, selection into importing exhibits complementarities across source markets. We exploit these complementarities to solve the firm's problem and estimate the model. Comparing counterfactual predictions to reduced-form evidence highlights the importance of interdependencies in firms' sourcing decisions across markets, which generate heterogeneous domestic sourcing responses to trade shocks.