Because people of high socioeconomic status are, on average, rated as more physically attractive than people of lower status, many correlations between one partner's appearance and the other partner's status are spurious and misconstrued.

“Women spend a lot more time trying to look good than men do,” McClintock said. “That creates a lot of mess in this data. If you don’t take that into account then you actually see there’s a lot of these guys who are partnered with women who are better looking than them, which is just because, on average, women are better looking. Men are partnering 'up' in attractiveness. And men earn more than women—we’ve got that 70-percent wage gap—so women marry 'up' in income. You’ve got to take these things into account before concluding that women are trading beauty for money.”

The study concludes that women aren’t really out for men with more wealth than themselves, nor are men looking for women who outshine them in beauty. Rather, hearteningly, people really are looking for ... compatibility and companionship. Finding those things is driven by matching one's strengths with a partner who’s similarly endowed, rather than trying to barter kindness for hotness, humor for conscientiousness, cultural savvy for handyman-ship, or graduate degrees for marketable skills.

At least partly because physically attractive individuals are treated preferentially by the world at large, they enjoy improved school performance, greater occupational success, and higher earnings. So these variables can be hard to isolate.

“It would be very hard to separate out class and attractiveness,” McClintock said, “because they’re just so fundamentally linked. I can’t control for that—but I don’t see how anybody could.”