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 offers a model of the interaction between composition of jobs and labour market regulation. Ex-post rent-sharing due to search frictions implies that ‘good’ jobs which have higher creation costs must pay higher wages. This wage differential distorts the composition of jobs, and in...

This paper offers and tests a theory of training whereby workers do not pay for general training they receive. The crucial ingredient in our model is that the current employer has superior information about the worker’s ability relative to other firms. This informational advantage gives the...

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...

An important component of the long-run cost of a war is the loss of human capital, suffered by children of schooling age who receive less education because of the war. This paper shows that in the European countries involved in World War II, children who were ten years old during the conflict...

This paper documents the existence of striking regional differences in the reported behaviour of employees working within the same firm, but in different Italian regions. In particular, the frequency of recorded and punished misconduct episodes is significantly higher among employees working in...

In the standard model of human capital with perfect labor markets, workers pay for general training. When labor market frictions compress the structure of wages, firms may invest in the general skills of their employees. The reason is that the distortion in the wage structure turns...

Becker's theory of human capital predicts that minimum wages should reduce training investments for affected workers, because they prevent these workers from taking wage cuts necessary to finance training. We show that when the assumption of perfectly competitive labour markets underlying this...