International Capital Mobility, Shadow Prices, and the Cost of Protection
研究小型开放经济中，当部分生产要素可跨国流动时，关税保护带来的福利损失。主要结论是：要素国际流动性必然提高保护成本；而外生要素流入对福利损失的影响取决于受保护商品是否密集使用外国要素。
This paper studies the welfare losses from tariff protection in a small open economy when some factors are internationally mobile. Our principal result is that international fictor mobility must raise the cost of protection. More specifically, the welfare loss resulting from a uniform increase in tariffs in a competitive small open economy is greater when tariff-induced international factor movements take place than when factors are internationally immobile. By contrast, an exogen1ous inflow of factors in the presence of tariffs may increase or reduce the welfare loss associated with protection, depending on whether or not the protected commodities use the foreign-owned factors intensively relative to domestically-owned factors. These results are proven for a very general specification of the economy's technology: in particular, no restrictions are placed on the degree of vertical integration in production, on the sectors into which factors are internationally mobile, or on the number of goods and factors. Our main result holds whether or not an increase in tariff rates leads the economy to specialise. In addition, we show how our results relate to earlier work on immiserising capital inflows and on negative shadow prices for factors of production, thus synthesizing a number of recent results within a common framework. The paper is organised as follows. In Section 2, we explain our framework and derive expressions for the welfare effects of tariffs when all factors are domestically owned and when some factors are foreign-owned but not internationally