Only one comment. To DF: Please read my book to avoid stating erroneous claims about what I said. I never claimed that there is no discrimination in labor markets. Indeed, most of the book analyzes the determinants of discrimination and then tries to measure discrimination against blacks. I do show why competition leads to less discrimination than monopoly. If Nancy Hopkins was irked by Summers interpretation of what I concluded, why didn't she stay to argue with him? Isn't that what one does at conferences?
Universities long had substantial discrimination against blacks, Jews, women, and other groups. So did banking and many other industries. But monopolistic industries had greater discrimination than competitive industries.