As the number of young children in daycare increases, people start to worry about the effect of early non-parental care. This is of special relevance as investments in the early periods of life are shown to be most important for a child’s long term development. Based on the German national...

We provide an overidentification test for a nonparametric treatment model where individuals are allowed to select into treatment based on unobserved gains. Our test can be used to test the validity of instruments in a framework with essential heterogeneity (Imbens and Angrist 1994). The...

Following the critique of Pinkse & Slade (2010) and Gibbons & Overman (2012), we develop an instrument for the estimation of local price effects of cell phone base stations (CPBS) in an urban area. The instrument is derived from the spatial structure of the network and technical and regulatory...

This paper examines the causal effect of volume on outcome on the example of patients with a hip fracture. We use an instrumental variable approach and consider both the practice-makes-perfect and selective-referral hypothesis as well as unobserved patient heterogeneity. Our results indicate...

This paper estimates the impact of elite school attendance on long-run outcomes including completed education, income and fertility. Our data consists of individuals born in the 1950s and educated in a UK district that assigned students to either elite or non-elite secondary schools. Using...