International migration, returns to education and increasing educational attainment of the native labor force. Can unskilled immigrants be preferred over skilled ones

This dissertation is a contribution to the academic and public debates about the economic consequences of international migration, theoretically and in the case of the particular experience of the United States. The basic hypothesis is that some selected characteristics of the international immigrants to the United States have been mostly driven by a secular trend of the native labor force to acquire higher levels of formal education. This interaction between a changing educational distribution of the native labor force and a correspondingly selected migration flow allows for a potentially bigger complementarity between the native and immigrant labor force than the one that can be expected in a context of stagnant educational levels of the native population.;I begin by reviewing the state of the literature along three strands: estimates of the economic impact of immigration; the process of self-selection of immigrants; and the interaction between immigration and the U.S. income distribution. Chapter 3 is a descriptive analysis of some trends in the educational distribution of the male labor force between the ages 18 and 64, observed in the five census years from 1960 to 2000. The data shows a significant decline in the fraction of native workers that are High School dropouts. This decline in both the absolute and relative numbers of natives in the lowest educational category is matched by an increase in the absolute number of immigrants in that category. An analysis at the state level shows a strong and increasing complementarity in the educational distribution of natives and immigrants.;The fourth chapter discusses in some detail the shortcomings in some of the identification strategies used in the literature to estimate the impact of a flow of foreign born workers. It also shows how some of the results in the literature might have been confounded with changes in the age (and, hence, experience) distribution of the native population due to the passage of the Baby Boom cohorts.;Chapter five presents a theoretical model that relates the evolution of the educational distribution of the labor force, to the relative wage of educated workers (or returns to education), to the consumption preferences of the native population, and to the role that immigrants can play in facilitating a match between the natives' preferences as workers and as consumers. The model shows that while the consumption possibilities depend on the endowment of factors, the desire to acquire higher levels of education (driven by the consumption value that education might have in addition to its value as an investment) might not be consistent with the consumption preferences of the native population. Based on the observed trends and the theoretical results, the final chapter discusses some policy implications of the previous analysis.