Import competition and firm refocusing
研究了进口竞争如何促使多产品企业剥离边缘产品、聚焦核心业务，利用美国上市公司产品数据验证了理论预测。
Abstract Recent theoretical work predicts a new margin of firm adjustment to trade liberalization; that is, multi‐product firms alter their product mix to focus on their core competencies in response to trade liberalization. Using detailed product data from U.S. public firms, I find strong empirical support for this prediction. Specifically, import competition leads multi‐product firms to drop peripheral products to refocus on core production. The weaker the linkages that a peripheral product shares with the core (as measured by the extent of joint sales, joint procurement, joint production, and joint sectorship), the more likely the peripheral product is to be divested in response to import competition.