Cao, N., Fragnière, E., Gauthier, J., Sapin, M., & Widmer, E. (2010). Optimizing the marriage market: An application of the linear assignment model European Journal of Operational Research, 202 (2), 547-553 DOI: 10.1016/j.ejor.2009.06.009
A lifetime ago – when I was still a university student in Italy – I bumped into an old article discussing marital matters in what for me was a very unusual way: modelling the utility functions of two partners getting intimate in bed (an occupation evocatively referred to as “activity X”…hummm!). “When love exists”, the author maintained, “each spouse’s marginal utility from x depends on both one’s own and one’s spouse’s consumption of hours in bed” (Hoffman, 1977).

Utility functions doin' the nasty (circa 1977)
If I indulge in reminescence here, it’s only to suggest that, after having spent my formative years dealing with such weirdness, the article I deal with today, published by the European Journal of Operational Research, shouldn’t come as a surprise. And yet, I’m still a little startled when I read of someone adopting a mathematical approach to marriage. Don’t get me wrong. I’m not saying that all mathematical approaches to social phenomena should be rebuked. I’m not that kind of person. Please allow me to develop on this.
Eric D. Widmer, a professor at the department of Sociology of the University of Geneva, and his team have produced an interesting research about optimizing the chances of finding the right partner. Based on a representative and longitudinal sample of 1074 Swiss couples (cohabiting and married), they estimated various objective functions corresponding to age, education, ethnicity, and previous divorce experience.
To be more precise:
- Evidence suggests that the soundest couples are those where the husband is 5 years older than his wife – the appeal of a mature man, I suppose. Or maybe, the charms of a younger woman to an older man, who knows…
- Successful couples show also another feature: wives have a higher level of education than their husbands. Definitely the charms of a young and smart Swiss woman play a role there… Or maybe some rigidities of the Swiss labour market which doesn’t seem to encourage women’s labour force participation to the same level as other developed countries. Or at least, didn’t seem back in 1999, when the family survey data started to be collected.
- Moreover, the couples less prone to divorce are those where both partners haven’t been through divorce before. The hypothesis is that those who never experienced divorce don’t know their ways around lawyers and paperwork, thus displaying a higher level of aversion for this uncertain course of action.
- Last but not least, the most successful couples are those where both partners are of Swiss nationality. Cultural homogamy triumphs! In your face, neighbour who married a hot Brazilian woman that left you after two years of love and torrid sex because she could not stand eat fondue with your friends in a ski resort every goddamn weekend! (This last bit, might or might not actually be in the article…).