Why Do Married Men Make So Much Money? By Bryan Caplan

If you’ve ever played around with wage or income data, you’ve probably noticed that married men make a lot more money than every other combo of gender and status. If your econometric model allows marriage to affect men’s and women’s earnings differently, you quickly explain a big chunk of the male-female and black-white gaps. But if you step away from the stats and think about the labor market, this huge marriage effect is a puzzle. What exactly is going on?

I just ran across an interesting twin study, “Are All the Good Men Married?,” that poses and answers this question. The punchline:

Our estimates suggest that marriage increases men’s wages by as much as 27%, and that little, if any, of the cross-sectional relationship between marriage and wages is due to selection.

Despite my fondness for twin studies, in this case I think I’d be more convinced by longitudinal data for a big sample of singletons. But even there, mightn’t men be marrying on the basis of their imminent prospects?