Kevin Drum throws some cold water on the conclusion of a recent study suggesting that assortative mating has been an important driver of rising income inequality:

Marriage patterns weren’t random in 1960 either, and the past popularity of “Cinderella marriages” is more myth than reality. In fact . . . assortative mating has actually increased only modestly since 1960. . . .

[R]ising income inequality isn’t really due to a rise in assortative mating per se. It’s mostly due to the simple fact that more women work outside the home today. After all, who a man marries doesn’t affect his household income much if his wife doesn’t have an outside job. But when women with college degrees all start working, it causes a big increase in upper class household incomes regardless of whether assortative mating has increased.

All true! But there have been some important changes from 1960 to 2005, per the data he presents. Assuming I’m reading the statistics right, there’s been a real change in the preferences of highly-educated women: the percentage of women with more than a college degree who married a high-school dropout dropped by over 70%, the percentage of women with a college degree who married a high-school dropout dropped by over 40%, and the percentage of women with more than a college degree who married a man with no more than a high school degree dropped by over 35%.

But the same is not true of the preferences of highly-educated men, which, in all three cases, are essentially unchanged from 1960 to 2005. Roughly the same percentage of highly-educated men in 2005 were willing to marry women with little education as was the case in 1960.

It’s not that men have remained more receptive to marrying below them in terms of education. Rather, women’s preferences have come to match men’s preferences over the 45 years in question. In 2005, the percentage of highly-educated women willing to marry men with a low education was essentially identical to the percentage of highly-educated men willing to marry women with a low education. In 1960, women were much more willing than men to “marry down” educationally-speaking.

That’s interesting, isn’t it – particularly given the fact that the percentage of women who complete college has soared since 1960. In 1960, men made up more than 60% of college degree-holders, versus under 40% women. By 2005, those percentages were nearly reversed.

Of course, it probably matters a whole lot more that the overall percentage of the population with a college degree has grown very substantially over the period in question, and that the overall percentage of the population that is married has dropped substantially over the period in question.

Regardless, I suspect it’s time to cue Hanna Rosin.