"Earnings differentials between married and unmarried [U.S.] men have been declining since the late 1960s. We consider two possible explanations for this decline: changes in the nature of selection into marriage; and changes in role specialization within marriage. Our analysis of changes in marriage differentials within cohorts supports only a small contribution of changes in selection. There is some evidence that differences in human-capital investment between married and unmarried men have fallen over time, but this effect has apparently been largely offset by increases in the return to that human capital." This is a revised version of a paper originally presented at the 1991 Annual Meeting of the Population Association of America.
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