David Lagakos

Selection, Agriculture and Cross-Country Productivity Differences

Cross-country labor productivity differences are larger in agriculture than in non-agriculture. We propose a new explanation for these patterns in which the self-selection of heterogeneous workers determines sector productivity. We formalize our theory in a general-equilibrium Roy model in which preferences feature a subsistence food requirement. In the model, subsistence requirements induce workers that are relatively unproductive at agricultural work to nonetheless select into the agriculture sector in poor countries. When parameterized, the model predicts that productivity differences are roughly twice as large in agriculture as non-agriculture even when countries differ by an economy-wide efficiency term that affects both sectors uniformly. (JEL J24, J31, J43, O11, O13, O40)

Life Cycle Wage Growth across Countries

This paper documents how life cycle wage growth varies across countries. We harmonize repeated cross-sectional surveys from a set of countries of all income levels and then measure how wages rise with potential experience. Our main finding is that experience-wage profiles are on average twice as steep in rich countries as in poor countries. In addition, more educated workers have steeper profiles than the less educated; this accounts for around one-third of cross-country differences in aggregate profiles. Our findings are consistent with theories in which workers in poor countries accumulate less human capital or face greater search frictions over the life cycle.

Life-Cycle Human Capital Accumulation Across Countries: Lessons From U.S. Immigrants

This paper assesses cross-country variation in life-cycle human capital accumulation, using new evidence from US immigrants. The returns to experience accumulated in an immigrant’s birth country before migrating are positively correlated with birth-country GDP per capita. To understand this fact, we build a model of life-cycle human capital accumulation that features three potential theories: differential human capital accumulation, differential selection, and differential skill loss. We use new data on the characteristics of immigrants and nonmigrants from a large set of countries to distinguish between these theories. The most likely theory is that immigrants from poor countries accumulate less human capital in their birth countries before migrating. Our findings imply that life-cycle human capital stocks are much larger in rich countries.