Date Added: Nov 2009
Using the large variation in the inflow of immigrants across US states the authors analyze the impact of immigration on state employment, average hours worked, physical capital accumulation and, most importantly, total factor productivity and its skill bias. They use the location of a state relative to the Mexican border and to the main ports of entry, as well as the existence of communities of immigrants before 1960, as instruments. They find no evidence that immigrants crowded-out employment and hours worked by natives. At the same time they find robust evidence that they increased total factor productivity, on the one hand, while they decreased capital intensity and the skill-bias of production technologies, on the other.