Of course, the average premium for higher education isn’t informative about
the distribution of that premium. As Lemieux (2006) points out, relative wages
among the highly educated have become much more dispersed since the mid
1970s. He suggests this is the result of a strong heterogeneity in the returns to
higher education. Much of the increase in labor market inequality is the result of
this heterogeneity and reflects higher wages at the very top of the distribution.
Wage growth has been higher for those with a college education in the United
States but higher still for those among the college educated with the graduate
and professional credentials.