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...

Although industrial plants, known as Toxic Release Inventory (TRI) sites, exist in every major city of the United States releasing billions of pounds of toxic substances annually, there is little evidence about how these pollutants might harm child development and children's long run outcomes....