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...

This Paper presents a tractable dynamic general equilibrium model that can explain cross-country empirical regularities in geographical mobility, unemployment and labour market institutions. Rational agents vote over unemployment insurance (UI), taking the dynamic distortionary effects of...