The best results on assortative mating and inequality I have seen

This paper studies the evolution of assortative mating in the permanent wage (the individual-specific component of wage) in the U.S., its role in the increase in family wage inequality, and the factors behind this evolution. I first document a substantial trend in assortative mating, as measured by the permanent wage correlation of couples, from 0.3 for families formed in the late 1960s to 0.52 for families formed in the late 1980s. I show that this trend accounts for more than one-third of the increase in family wage inequality across these cohorts of families. I then argue that the increase in marriage age across these cohorts contributed to the assortative mating and thus to the rising inequality. Individuals face a large degree of uncertainty about their permanent wages early in their careers. If they marry early, as most individuals in the late 1960s did, this uncertainty leads to weak marital sorting along permanent wage. But when marriage is delayed, as in the late 1980s, the sorting becomes stronger due to the quick resolution of this uncertainty with work experience. After providing reduced-form evidence on the impact of marriage age, I build and estimate a marriage model with wage uncertainty and show that the increase in marriage age can explain almost 80% of the increase in assortative mating.

That is from the job market paper of Alparslan Tuncay, from the University of Chicago.


Higher education is based on physically sorting people and forming segregated social peer groups accordingly. Surely, that deserves a mention.

I am sure it gets one, but he says another factor doesn't leave as much to explain as you might think.

That too has changed over time. With the opening of universities we’ll get less sorting. I’d also be willing to test this thesis: the effects on income distribution in the Ivey league exceeds state flagships which vastly exceeds state regionals and community colleges.

'Higher education is based on physically sorting people '

You just might have heard about online degree programs from universities, right? They are going to be a big thing, I've heard.

Mating is basically always assortive as long as there exists anything like choice and mate competition, but with a younger age of marriage, it will be assortive along different dimensions: instead of individual career potential, it would have been stuff like social group, family, physical attractiveness, personality, etc.

On the inequality dimension, it's an interesting question whether you want a relatively more egalitarian mixture, or higher peaks and closer matches. On the egalitarian side, you get fewer people living with no proximity to competence, which will save a lot of people a lot of trouble. Of course on the other hand it means fewer power couples who achieve great things together. Lower assortive mating probably leads to a more cohesive social group, and there are other reasons to prefer lower marriage age.

While equality is generally a good thing, to focus on it as a metric in general is a dangerous thing, because there are so many ways to make the world less equal that destroy social capital and make the world worse overall. It might be more prudent to focus more directly on the holistic problem of social capital, finding ways to minimize the downsides of inequality, rather than minimizing the inequality itself.

Well said, +1

Associative mating will eliminate incels from the gene pool. This is good for society. Unfortunately though incels have been fighting back to bloody effect.

As a quibble you can get a lot of assortativity without any much mate choice or competition (in the sense of individuals competing with each other) at all - arranged marriages. It's popular at the moment to think of assortativity as a product of changes in divorce, university, income inequality. In the near term, probably. But things could be quite assortative in the old school world where young individuals didn't have so much choice and family had a bigger say. (Though they might have selected to produce better, or worse, people.)

The counterfactual would be whether marriage age would have increased if real wages had increased more.

I'm a cuck!

There is a lot of truth to this. We went from the conventional 1970's style families to what I call the "yuppie" style family among the upper-middle class by the late 1980's. The latter is the husband who might be a management consultant married to a wife who is a lawyer, who have their one or two children in their late 30's, and live in a mcmansion in development named Cold Creek Estates.

Close to my experience, although among the truly upper class (partners at said management consultancies, and the like) increasing incomes are correlated with increasing numbers of children. When you can hire multiple nannies to care for the kids at all hours, children become an idealized escape and hope for the parents without material sacrifice.

It does seem the families with lots of kids are either very poor or very rich. Hard to have 5 kids in the middle class anymore.

I had four children, we managed to raise them in a middle class neighborhood with good schools and went on vacations. But we did not live in a large house, bought practical used minivans, used or cheap furniture, and used or at best clothes at Sears. We only went to the dollar movies, and the only luxury was a several hundred book collection and subscriptions to Discover and Scientific American. I believe most younger people simply can't stand having money and spend it as fast as they can. Nowadays i drive a 10 year old car with a small diesel engine and it does fine. The young people around me drive super fat luxury SUVs they dont know how to park, some even have BMWs and Mercedes. And then they complain they cant have more than one child.

Fernando I think you are heroic and I suspect your children’s values are of an unusual moral highground

Well, I'd rather the rich have more kids than the poor. Who needs an expanded underclass?

At some point if the 0.001% only breed with the 0.001%, then problems of inbreeding will manifest and the realities of biology will rear its ugly head.

Abelard "Who needs an expanded underclass?"

The Democrats, which is why they keep importing them from Honduras, Guatemala, Nicaragua, and El Salvador. You can never have too many "Latinos" in the voting booth.

Eh. Most MR regulars think within country developed country inequality concerns are overblown.

That seems like it implies a larger "underclass" is either acceptable or desirable. As well as a larger economic "overclass". (If we don't like having the relative poor about, well, redistribution helps with that.)

I wonder if the shift improved outcomes for people from poor families who have high earnings. Conversely, a screw up from a rich family is less attractive when they are older than younger.

At 16, parent income is a more powerful heuristic than at 25. Although this shift may be bad for mobility within a generation, it seems plausible that it enhances multi-generational mobility.

A catch around this is that a poor guy from a rich family would tend (on average) to have the "rich genes" of his family (to pass on to kids), and the poor outcomes from environment (won't pass on to kids).

Conversely, the rich guy from the poor family is more likely to have "poor genes", and be rich for environmental and individual reasons the kids won't inherit.

So if you have a pure tradeoff between achieved and familial status, it might be a wash in terms of heritable assortativity (increasing concentration of genetic "eliteness" within some people).

Of course the superior strategy (if you want to maximize your kids genetic "eliteness") is probably to use both forms of information in an optimal way. But people may not always naturally do so if the key drivers of pairing up in our society are very individualized (the incentives are to care about your husbands/wifes achieved status, and socialization happens in a very open way without much regard to family backgrounds).

Everyone's downwardly mobile in America. Everyone I know is living a shittier life than his/her parents lived. I'm glad that there's so much Growth in Ethiopia and Nigeria though, I guess. Or China and other similarly bizarre places that inspire Niven & Pournelle type novels in which alien psychologies deterministically produce interstellar warfare. I hear there's Growth going on somewhere, anyway. I think that someone wrote a book about it.

A big question is whether the early marriage of the 1950s-1960s was representative of previous generations, or was it an anomalous product of the historically favorable family formation affordability of the postwar era.

+1, my Greatest-Gen grandparents were 20 and 22 when they married in 1944 and (like a lot of Catholic families of the era) had 5 kids over the ensuing 14 years, but both of their parents (all born in the 1890s) had married in their mid-late 20s, with two and three children respectively.

That's my impression: the very early marriage ages of the 1950s-1960s were rare.

How about the mating behavior of students with high college debt and poor job prospects.

They probably have sex but do not marry.

Associative mating will eliminate incels from the gene pool. This is good for society. Unfortunately though incels have been fighting back to bloody effect.

Since wives often didn't work, or worked only part time at low wage jobs, I don't see how we can discuss long term trends in alternative mating.

Mating could still be highly assortative even if everyone in the population were unemployed, subsisted on free money dropped down from the heavens by the gods, and lived out their days pursuing hobbies and interests. More so, even.

Lack of female employment in the past doesn't itself imply a lack of assortative mating. Just that it is not happening by matching female employment status with male in the same professions, but in matching females and males who are similar status in distinct sex specific tracks.

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