The role of friends in the US opioid epidemic is examined. Using data from the National Longitudinal Survey of Adolescent Health (Add Health), adults aged 25-34 and their high school best friends are focused on. An instrumental variable technique is employed to estimate peer effects in opioid...

Secondary schools in the developed world differ in the degree of differentiation and in the first age of selection of pupils into different tracks. In this paper, we account for the heterogeneity of tracking time with a simple stochastic model which conjugates the returns from specialization...