27th
Marriage and matching theory
A great friend of mine, Shri Mahesh, posted recently on the topic of choosing a spouse. The two points of discussion:
- The merits of “settling” (or, as Shri prefers, compromising) when choosing a mate
- The apparent surplus of “high-quality single women” in their thirties, versus high-quality men of the same age
My figurative ears perked up at the post because it reflected pretty strongly on one of the chapters in my doctoral dissertation - with the incredibly sexy title “Dynamic Two-Sided Matching with Identical Preferences”, which looks good in a thesis but is less impressive in a blog post.
Translated into plain English, the primary model of the chapter looked at a situation where men and women periodically meet and decide whether to get married or not. (“Dynamic” is the “periodically” part; men and women are the “Two-Sided” part; and meeting & deciding whether to get married is the “Matching” part. Don’t worry about the Identical Preferences.)
This model, it turns out, predicts something exactly opposite from what Shri’s women do. High-quality women do wait for high-quality men, but they’re likely to get married faster than lower-quality women. (Without going into the mathematics, the idea is that the relative opportunity cost of rejecting a similar-quality person is higher for the best people, so they have stronger incentives to take a decent partner now rather than wait for a perfect partner.)
Taking Shri’s observation - the surplus of great single women in their 30’s - as granted, one wonders why it’s the case. The article she cites suggests that many high-quality women aren’t “bidding as aggressively”, or “hold out too long”, compared to lower-quality women. This by itself can’t be enough, though - there has to be some difference between male and female mate-choosing behavior (symmetrical behavior would lead to a symmetrical outcome). Perhaps the point extends to “men of different qualities are similarly decisive, whereas high-quality women are significantly choosier than lower-quality women.”
There are lots of other potential explanations, too.
- Maybe high-quality women have significantly better “outside options” (economic lingo for what you get if you don’t “reach agreement” in a negotiation - in this case, get married), and should thus be much more selective. (Again, we’d need to explain why the same thing isn’t true for men; maybe the delta between getting married vs. staying single is relatively constant for men across quality levels, but varies strongly for women.)
- Perhaps the “great single women in their 30’s” are overestimating their quality from mens’ perspectives, whereas men have a more accurate gauge of how much women value them.
- Maybe women are more patient and can afford to hold out longer, looking for a better match.
- … and, with certainty, this whole notion of a single “quality ranking” is highly flawed.
In any case, Shri - thanks for helping me reminisce about my days as a game theorist. :)
Disclosure: I got married pretty early - 24 - to a very high-quality woman.
