In this paper, we assess whether welfare reform affects earnings only through mean impacts that are constant within but vary across subgroups. This is important because researchers interested in treatment effect heterogeneity typically restrict their attention to estimating mean impacts that are...

While patent systems have been widely used both historically and internationally, there is nonetheless a tremendous amount of controversy over whether patent systems – in practice – improve the alignment between private returns and social contributions. In this paper, I describe three...

We study the effects of peer gender composition, a proxy for female-friendliness of environment, in STEM doctoral programs on persistence and degree completion. Leveraging unique new data and quasi-random variation in gender composition across cohorts within programs, we show that women entering...

Education policy makers have struggled for decades with the question of how to best serve high ability K‐12 students. As in the debate over selective college admissions, a key issue is targeting. Should gifted and talented programs be allocated on the basis of cognitive ability, or a broader...

We test the effect of performance-based incentives on educational achievement in a low-performing school district using a randomized field experiment. High school freshmen were provided monthly financial incentives for meeting an achievement standard based on multiple measures of performance...