Raaum, Oddbjørn; Aabø, Tom Erik - In: Nordic Journal of Political Economy 26 (2000), pp. 95-113
A large representative sample of Norwegian twins is used to estimate the causal effect of schooling on earnings in Norway, separately for men and women. The within-twin-pair estimates reveal that standard cross section (OLS) estimates of the schooling effect on male hourly earnings are biased...