We exploit rules of class formation to identify the causal effect of increasing the number of immigrants in a classroom on natives test scores, keeping class size constant (Pure Composition Effect). We explain why this is a relevant policy parameter although it has been neglected so far. We show...

We study the contribution of health-related behaviors to the health-education gradient by distinguishing between short-run and long-run mediating effects: while in the former only current or lagged behaviors are taken into account, in the latter we consider the entire history of behaviors. We...