Heterogeneity in returns to schooling: Econometric evidence from Ethiopia

The paper investigates whether returns to schooling in Ethiopia vary across the wages distribution of individuals. To do so it adopts an instrumental variables quantile regression framework that allows for both endogeneity of schooling resulting from unmeasured ability, and possible heterogeneity in the impact of schooling. The empirical estimates indicate that education contributes more to the earnings of the individuals at a lower end of the income distribution. Under the assumption that the wage and ability distributions are related, this result is consistent with the notion that education and ability are substitutes.