We examine the generalizability of internally valid estimates of causal effects in a fixed population over time when that population is subject to aggregate shocks. This temporal external validity is shown to depend upon the distribution of the aggregate shocks and the interaction between these...

This paper studies how individuals "believe" human capital investments will affect their future career and family life. We conducted a survey of high-ability currently enrolled college students and elicited beliefs about how their choice of college major, and whether to complete their degree at...

Existing growth research provides little explanation for the very large differences in long-run growth performance across OECD countries. We show that cognitive skills can account for growth differences within the OECD, whereas a range of economic institutions and quantitative measures of...

This essay proposes a set of non-econometric tests using data on wage structure, school resource costs, public expenditures, taxes, and rates of return to explain anomalies in which richer political units deliver less education than poorer ones. Both the anomalies of education history, and its...

This paper studies the nature and impact of credit constraints in the market for human capital. We derive endogenous constraints from the design of government student loan programs and from the limited repayment incentives in private lending markets. These constraints imply cross-sectional...

This paper develops a model of crime in which human capital increases the opportunity cost of crime from foregone work and expected costs associated with incarceration. Older, more intelligent, and more educated adults should commit fewer street (unskilled) crimes. White collar crimes decline...