We examine the relationship between wages and skill requirements in a sample of over 50,000 managers in 39 companies between 1986 and 1992. The data include an unusually good measure of job requirements and skills that can proxy for human capital. We find that wage inequality increased both...

A large literature examines demand-side barriers to product adoption. In this paper, we examine supply-side barriers in a setting with limited contract enforcement. We model the relationship between a distributor and its credit-constrained vendors. We show that the optimal self-enforcing...

We study how a regulator can best target inspections. Our case study is a US Occupational Safety and Health Administration (OSHA) program that randomly allocated some inspections. On average, each inspection averted 2.4 serious injuries (9%) over the next five years. We use new machine learning...

Basic sanitation and hygiene can prevent roughly a million deaths a year. This study examines the rapid prototyping of a pilot school-based handwashing, safe water, and sanitation program in Chennai, India. Our content analysis identified challenges in the classroom (Localization; Curriculum...

Basic sanitation and hygiene can prevent roughly a million deaths a year. This study examines the rapid prototyping of a pilot school-based handwashing, safe water, and sanitation program in Chennai, India. Our content analysis identified challenges in the classroom (Localization; Curriculum...

In many randomized trials, subjects enter the sample sequentially. Because the covariates for all units are not known in advance, standard methods of stratification do not apply. We describe and assess the method of DA-optimal sequential allocation (Atkinson, 1982) for balancing stratification...