In the early 1970s, Gary Becker was hitting stride, knocking out economic theories of crime, the allocation of time, discrimination, marriage, and children in rapid succession. His theory of marriage treated the marriage scene like any other economic market, cleared by a price. Men bid for women, and women bid for men. In a shallow view of his model, women sought handsome men, and men beautiful women, and beauty was not in the eye of the beholder. Becker’s main theorem — whose proof he credits to my esteemed colleague Buz Brock — found that the men and women efficiently sorted by their beauty when their beauties were complements.

I visited the Cowles Foundation at Yale for the winter of 2006, and taught a senior elective course. Seven fortunate students took my seminar in information economics. One impressive woman student — who organized the gay and lesbian social scene — asked whether the shallow view of Becker’s model was so unrealistic. Did babes match with hunks?

We brainstormed on data sources and settled on two new web sites: and Facebook allowed users to indicate with whom they were “in a relationship with”. Facebook was still new, and not yet open to all email addresses. So the student asked her friends at various campuses across  America for their logins. And so began our stealth project. Hundreds of photos of matched men and women were downloaded, and then uploaded to HotOrNot, all on the sly. HotOrNot afforded us the average evaluation of about 200 women for every man, and 2000 men for every woman.

The result: Regressing straight men’s or women’s hotness on their partner’s hotness gave a highly significant fit, with a slope of about 0.7 — so that a man rising in hotness from 7 to 8 expects his partner to rise by 0.7 points. But sorting was far closer for gays and lesbians, with a slope for each of about 0.9. As Becker implied, beauty is income in this meat market, and the “richest” men match with the “richest” women.