  In this paper, we extend Gary Becker's empirical analysis of the marriage
market to same-sex couples. Becker's theory rationalizes the well-known
phenomenon of homogamy among different-sex couples: individuals mate with their
likes because many characteristics, such as education, consumption behaviour,
desire to nurture children, religion, etc., exhibit strong complementarities in
the household production function. However, because of asymmetries in the
distributions of male and female characteristics, men and women may need to
marry "up" or "down" according to the relative shortage of their
characteristics among the populations of men and women. Yet, among same-sex
couples, this limitation does not exist as partners are drawn from the same
population, and thus the theory of assortative mating would boldly predict that
individuals will choose a partner with nearly identical characteristics.
Empirical evidence suggests a very different picture: a robust stylized fact is
that the correlation of the characteristics is in fact weaker among same-sex
couples. In this paper, we build an equilibrium model of same-sex marriage
market which allows for straightforward identification of the gains to
marriage. We estimate the model with 2008-2012 ACS data on California and show
that positive assortative mating is weaker for homosexuals than for
heterosexuals with respect to age and race. Our results suggest that positive
assortative mating with respect to education is stronger among lesbians, and
not significantly different when comparing gay men and married different-sex
couples. As regards labor market outcomes, such as hourly wages and working
hours, we find some indications that the process of specialization within the
household mainly applies to different-sex couples.
