What Do We Really Know about Protection before the Great Depression: Evidence from Italy
指出传统用关税收入与进口额之比衡量保护程度有偏差，通过计算意大利统一至大萧条期间的贸易限制指数，发现长期福利损失小，且保护措施测量方式影响贸易政策与经济增长因果关系的结论。
The impact of protection on economic growth has enjoyed a revival in recent times, with the publication of a number of comparative quantitative papers. They all share a common weakness: they measure protection as the ratio of custom revenues to import value, which biases results if demand for imports is not perfectly inelastic. In this article, we show that the measure of protection matters. We estimate the James Anderson and Peter Neary (2005) Trade Restrictiveness Index for Italy from unification to the Great Depression. We suggest a different interpretation of some key moments of Italian trade policy and we show that the aggregate welfare losses were small in the long run and mostly related to protection on sugar in the 1880s and 1890s. We document that using different measures of protection affects results of the causal relation between trade policy on economic growth in Italy and in the United States. Accordingly, we argue that a systematic re-estimating of protection in the economic history of trade policy is needed.