Knowledge that Transforms

This paper uses eleven years of administrative data from North Carolina public high schools to examine the extent to which the allocation of teachers within and across public high schools is contributing to inequality in student test score performance. The existence of nearly 3,500 teacher transfers allows separate identifica-tion of each teacher’s quality from other school-level factors. I find that teaching quality is fairly equitably distributed both within and across high schools: students among the bottom (top) decile of a student back-ground index are taught by teachers who are, on average, at the 41st (57th) percentile of the value-added distribution. I have greatly benefited from the input of Joseph Altonji, as well as Fabian Lange, Melissa Tartari, Costas Meghir, Lisa Kahn, Amanda Kowalski, and several anonymous referees. I also thank Mark Klee, Matthew Johnson, Priyanka

In a stochastic Becker marriage model (Choo and Siow), supermodularity of the match output function implies stochastic positive assortative matching (PAM): the equilibrium marriage matching distribution has all positive local log odds ratios or is totally positive of order 2 (TP2). The Choo-Siow model rationalizes the practice of studying PAM independent of population vectors and marriage rates and conditional on other spousal characteristics. Using white married couples in their 30s from the 2000 US Census, spousal educational matching generally obeyed TP2. Between 1970 and 2000, there was no general increase in PAM. There was increased homogamy in spousal education matching.

Many believe that classroom interactions play an important role in students’ academic achievement, but there is little evidence on peer effects within subclassroom groups. We exploit random seat assignment in a Chinese middle school to estimate how the gender of neighboring students affects a student’s academic achievement. We find that being surrounded by five females rather than five males increases a female’s test scores by 0.2–0.3 standard deviations but has no significant effects on a male’s test scores. These results suggest a low-cost way to potentially improve performance within the world’s largest school system.

This paper examines how high-skilled immigrants contribute to knowledge diffusion using a rich data set of Russian scientists and US citations to Soviet-era publications. Analysis of a panel of US cities and scientific fields shows that citations to Soviet-era work increased significantly with the arrival of immigrants. A difference-in-differences analysis with matched paper pairs also shows that after Russian scientists moved to the United States, citations to their Soviet-era papers increased relative to control papers. Both strategies reveal scientific field–specific effects. Ideas in high-impact papers and papers previously accessible to US scientists were the most likely to “spill over” to natives.

College graduates do not always pursue careers related to their major. Science majors working in jobs unrelated to their field of study earn approximately 30% lower wages than those working in related jobs. We develop a structural model of major choice and labor market outcomes that allows for skill uncertainty and differential accumulation of human capital across major. Our findings confirm that the average return to obtaining a science degree and working in a related job remains close to 30%. We also find that individuals are uncertain about their future productivity at the time of the college major decision.

This paper documents that the dynamics of occupational segregation are highly nonlinear and exhibit tipping patterns. Occupations experience discontinuous declines in net male employment growth at tipping points ranging from 25% to 45% (from 13% to 30%) female in white-collar (blue-collar) occupations from 1940 to 1990. These patterns appear consistent with a Schelling (1971) social interaction model where tipping results from male preferences toward the fraction female in their occupation. Supporting the model’s predictions, evidence from the General Social Survey indicates that tipping points are lower in regions where males hold more sexist attitudes toward the appropriate role of women.

We study the impact of skilled immigrants on the employment structures of US firms using matched employer-employee data. Unlike most previous work, we use the firm as the lens of analysis to account for greater heterogeneity and the fact that many skilled immigrant admissions are driven by firms themselves (e.g., the H-1B visa). OLS and IV specifications show rising overall employment of skilled workers with increased skilled immigrant employment by the firm. Employment expansion is greater for young natives than for their older counterparts. The departure rates for older workers relative to younger workers appear highest for those in STEM occupations.

This paper analyzes how changes in the skill mix of local labor supply are absorbed by the economy, distinguishing between three adjustment mechanisms: wages, expansion in size of those production units using the more abundant skill group more intensively, and more intensive use of the more abundant skill group within production units. We contribute to the literature by analyzing these adjustments on the firm rather than industry level, using German administrative data. We show that most adjustments occur within firms through changes in relative factor intensities and that firms entering and exiting the market are an important additional absorption mechanism.

In 1997, the ACT increased the number of free score reports it provided to students from three to four, maintaining a $6 marginal cost for each additional report. In response to this $6 cost change, ACT-takers sent many more score reports and applications relative to SAT-takers. They widened the range of colleges they sent scores to, and low-income ACT-takers attended more-selective colleges. Back-of-the-envelope calculations suggest that the policy substantially increased low-income students’ expected earnings. This sizable behavioral change in response to such a small cost change suggests that in this setting, small policy perturbations can have large effects on welfare.

How and by how much do supervisors enhance worker productivity? Using a company-based data set on the productivity of technology-based services workers, we estimate supervisor effects and find them to be large. Replacing a boss who is in the lower 10% of boss quality with one who is in the upper 10% of boss quality increases a team’s total output by more than adding one worker to a nine-member team would. Workers assigned to better bosses are less likely to leave the firm. A separate normalization implies that the average boss is about 1.75 times as productive as the average worker.