Although surveys show that traditional ordering of average wages--i.e. higher earnings with higher schooling and concave age-wage profiles--have not changed during the past three decades, the actual size of the wage differentials measured by education or by work experience has varied from peak...

The "human capital earnings function," in which earnings are expressed as a quadratic in potential experience, is probably the most widely accepted empirical specification in economics. In spite of its widespread acceptance, the human capital earnings function provides a very poor approximation...