Knowledge that Transforms

This study examines changes in returns to formal education and cognitive skills over the past 20 years using the 1979 and 1997 waves of the National Longitudinal Survey of Youth. We show that cognitive skills had a 30%–50% larger effect on wages in the 1980s than in the 2000s. Returns to education were higher in the 2000s. These developments are not explained by changing distributions of workers’ observable characteristics or by changing labor market structure. We show that the decline in returns to ability can be attributed to differences in the growth rate of technology between the 1980s and 2000s.

We investigate how the interplay between manager and worker origin affects hiring patterns, job separations, and wages. Numerous specifications utilizing a longitudinal matched employer-employee database including 70,000 establishments consistently show that managers are substantially more likely to hire workers of their own origin. Workers who share an origin with their managers earn higher wages and have lower separation rates than dissimilar workers, but this pattern is driven by differences in unobserved worker characteristics. Our findings indicate that the sorting patterns are more likely to be explained by profit-maximizing concerns than by preference-based discrimination.

We use a within-subjects experiment with math and word tasks to show that relative performance feedback moves high-ability females toward more competitive forms of compensation, moves low-ability men toward less competitive forms, and eliminates gender differences in choices. We also examine females across the menstrual cycle and find that women in the high-hormone phase are more willing to compete than women in the low-hormone phase. There are no significant differences between choices after subjects receive feedback. Thus, biological differences lead to economically significant differences, but the impact of those differences can be lowered through relative performance information.

We estimate a dynamic learning model of college dropout, taking advantage of unique expectations data to greatly reduce our reliance on standard assumptions. Our simulations show that 45% of dropout in the first 2 years of college can be attributed to what students learn about their academic performance, with this type of learning playing a smaller role later in college. Poorly performing students tend to leave because staying is not worthwhile rather than because they are at risk of failing out of school. Poor performance substantially decreases the enjoyability of school and substantially influences beliefs about postcollege earnings.

Since the seminal work of Stigler in 1962, economists have recognized that information is costly to acquire and leads to “search frictions.” Growth in online search has lowered the cost of information acquisition. We analyze the expansion of the website Craigslist, which allows users to post job and housing ads. Exploiting the sharp geographic and temporal variation in the availability of online search induced by Craigslist, we produce three key findings: Craigslist significantly lowered classified job advertisements in newspapers, caused a significant reduction in the apartment and house rental vacancy rate, and had no effect on the unemployment rate.

This article analyzes the impact of five major expansions in maternity leave coverage in Germany on mothers’ labor market outcomes after childbirth. To identify the causal impact of the reforms, we use a difference-in-difference design that compares labor market outcomes of mothers who give birth shortly before and shortly after a change in maternity leave legislation in years of policy changes and years when no changes have taken place. Each expansion in leave coverage reduced mothers’ postbirth employment rates in the short run. The longer-run effects of the expansions on mothers’ postbirth labor market outcomes are, however, small.

I combine a regression discontinuity design with rich data on academic and labor market outcomes for a large sample of Florida students to estimate the returns to college admission for academically marginal students. Students with grades just above a threshold for admissions eligibility at a large public university in Florida are much more likely to attend any university than below-threshold students. The marginal admission yields earnings gains of 22% between 8 and 14 years after high school completion. These gains outstrip the costs of college attendance, and they are largest for male students and free-lunch recipients.

The allocation of children’s time among different activities may be important for cognitive and noncognitive development. Here, we exploit time use diaries from the Longitudinal Study of Australian Children to study the effects of time allocation. By doing so, we characterize the trade-off between different activities to which a child is exposed. On the one hand, our results suggest that time spent in educational activities, particularly with parents, is the most productive input for cognitive skill development. On the other hand, noncognitive skills appear insensitive to alternative time allocations. Instead, they are greatly affected by the mother’s parenting style.

We estimate the impacts of temperature on time allocation by exploiting plausibly exogenous variation in temperature over time within counties. Temperature increases at the higher end of the distribution reduce hours worked in industries with high exposure to climate and reduce time allocated to outdoor leisure for the nonemployed, with this time reallocated to indoor leisure. At the lower end of the distribution, time allocated to labor is nonresponsive to temperature increases, but outdoor leisure increases while indoor leisure decreases as temperature warms. We also find suggestive evidence of short-run adaptation to higher temperatures through temporal substitutions and acclimatization.

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