Monday, 15 March 2010

Marriage as an optimisation problem

I do not read the UK national newspaper "Daily Mail" very often, but I bought a copy on Thursday 4th March 2010 to read on a rail journey. To my astonishment, there was a whole page based on a research paper in the European Journal Of O.R.

The paper was never cited, so I had to use the journal's webpage to find the item concerned. Details are below.

The author of the newspaper's article, Mark Barrowcliffe, used his marriage as a counter-example to the conclusions of the EJOR article. He concludes:

"The elements of love are nothing more complicated than passion, companionship and mutual respect. And if you've got those in abundance, who really gives a spud what the European Journal of Operational Research thinks anyway?"

Personally, I remember the question which was asked by modellers in O.R. during the second world war. The model in question was about the optimal size of convoys, to minimise losses. Before the solution was put into practice, the team were asked "Would you trust your children to cross the Atlantic in such a convoy?" Maybe the researchers should have asked "Would you like your marriage to be organised on the basis of a mathematical model?"

European Journal of Operational Research, Volume 202, Issue 2, 16 April 2010, Pages 547-553
Innovative Applications of O.R.
Optimizing the marriage market: An application of the linear assignment model

Nguyen Vi Cao, Emmanuel Fragnière, Jacques-Antoine Gauthier, Marlène Sapin, and Eric D. Widmer

aHaute Ecole de Gestion de Genève, 7, rte de Drize, 1227 Carouge, Switzerland

bUniversité de Lausanne, Institut des trajectoires biographiques/Centre, PaVie Bâtiment Provence, 1015 Lausanne, Switzerland

cUniversité de Genève, Département de sociologie, Uni Mail, 40, Bd. Pont-d’Arve, 1211 Genève 4, Switzerland

dSwiss Foundation for Research in Social Sciences, c/o Université de Lausanne, Bâtiment Vidy, 1015 Lausanne, Switzerland

eUniversité de Lausanne, Centre de recherche Méthodologie, inégalités et changement social (MISC), Bâtiment de Vidy, 1015 Lausanne, Switzerland

fUniversity of Bath, School of Management, BA2 7AY, UK
Received 23 January 2008;
accepted 3 June 2009.
Available online 18 June 2009.


Research shows that the success of marriages and other intimate partnerships depends on objective attributes such as differences in age, cultural background, and educational level. This article proposes a mathematical approach to optimizing marriage by allocating spouses in such a way as to reduce the likelihood of divorce or separation. To produce our optimization model, we use the assumption of a central “agency” that would coordinate the matching of couples. Based on a representative and longitudinal sample of 1074 cohabiting and married couples living in Switzerland, we estimate various objective functions corresponding to age, education, ethnicity, and prior divorce concerning every possible combination of men and women. Our results show that the current state of previous termmarriagesnext term or partnerships is well below the social optimum. We reallocate approximately 68% of individuals (7 out of 10) to a new couple that we posit has a higher likelihood of survival. From this selection of new partners, we obtain our final “optimal” solutions, with a 21% reduction in the objective function.

Keywords: Couples matching; Divorce; Linear assignment model; Marriage market; OR in societal problem analysis