Let me return to our discussion a few weeks ago of the gender gap in college enrollments, and respond to a few of the many interesting comments. The gap in male-female median earnings is indeed less than in mean earnings because the distribution of male earnings is more skewed to the right. The greater skewness in male earnings is due to their greater variance in "skills", and to an interaction between skills and market demand. For a model of this kind (but not applied to male-female earnings differences), see my Human Capital.
To clarify my position on affirmative action for men and for various other groups, I am not claiming that non-hispanic whites do not have any desire to have African American, Latinos, and other minorities in their classes. Surely, many of them do, but I do claim that the desire of women to have a significant fraction of male students in the colleges they attend, and visa versa for men, is on the whole greater than the desire to have many members of these minority groups.
For reasons given in previous posts, I am against all government-enforced affirmative action admission-programs. Still, colleges should be free to choose their admission policies in the competitive higher education market of the United States. This includes the freedom to bring in more male students to balance a majority of female students. It also very definitely includes freedom of schools to show preference for minority students. We can argue about whether colleges should want to do this, but I leave that up to them to decide. However, it is unwise for governments to force such actions on colleges, as long as there is sufficient competition among colleges. There is enough competition in American higher education (but not in higher education in many other countries).
The war on drugs is certainly a factor, indeed I believe an important factor, in the low rate of high school completion among African-American males, and also in the higher education of African American females. The comment posted gives a good discussion of the reasons why. While there are many other forces involved, such as unstable families, the war on drugs is in principle the easiest to correct simply by legalizing drugs.
Part of the source in the gender gap in earnings during the past couple of decades is that many males who would be at the low end of the earnings distribution have dropped out of the labor force. However, there is still a sizeable gender gap in earnings even after correcting for the high male drop out rates. Moreover, the same type of selectivity applies to women since college educated women are more likely to work than women with lesser education.
Some of you in effect argue that colleges should take account of the greater variability in performance of men as well as their lower average performance. I agree and stated that in my post.