Using a dataset that allows consistent cross-country comparisons the non-linearity in a conventional earnings equation is tested with respect to schooling. The findings suggest that the assumption of linearity is not robust and that there are well-determined positive returns to the completion of...

This article investigates whether the returns to education vary with the level of cognitive ability. Unlike much of the literature, this article finds that the return to schooling is lower for those with higher cognitive ability indicating that education can act as a substitute for observed...