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 use a quantile regression framework to investigate the degree to which work-related training affects the location, scale and shape of the conditional wage distribution. Human capital theory suggests that the percentage returns to training investments will be the same across the conditional...

Several recent studies based on 'exogenous' sources of variation in education outcomes show Instrumental Variables (IV) estimates of returns to schooling that are substantially higher than the corresponding Ordinary Least Squares (OLS) estimates. Card (1995a) suggests that these results can be...