Modeling an Immigration Shock

In this paper, we model an overlapping generation economy affected by an unexpected immigration shock and determine how households would insure themselves against "immigration risks" efficiently. We use the model to study the impact of immigration on (i) the welfare of various generations, (ii) the distributions of income among factors of production, and (iii) the optimal design of the intergenerational welfare state. In particular, we construct a system of public education and public pensions that mimics efficient complete market allocation. We also show the impact of immigration shocks in a small open economy. In this case, our model suggests that the external capital flows can act as substitutes for the missing private insurance markets. Our analysis delivers a set of predictions that we find useful for understanding certain aspects of the Spanish experience during 1996 and 2007.