Randomized experiments provide policy relevant treatment effects if there are no spillovers between participants and nonparticipants. We show that this assumption is violated for a Danish activation program for unemployed workers. Using a difference-in-difference model we show that the...

Workers acquire skills through formal schooling, through training provided by governments, and through training provided by firms. This chapter reviews, synthesizes, and augments the literature on the last of these, which has languished in recent years despite the sizable contribution of firm...

We employ a large social experiment combined with register-based data allowing for up to 12-year follow-up to evaluate a long-lasting employer-sponsored health and well-being program. We show that employees at treated worksites receive fewer consultations from their primary care physician and...

This paper examines the effects of daily outdoor air pollution variation on student test scores. Using Danish register data for all elementary and lower secondary students, we link home addresses to a 1 km x 1 km pollution grid to measure test day and lifetime pollution exposure. An increase in...