Thursday, March 06, 2014

Not (all) in our genes?

Economic historian Greg Clark describes his latest research (and new book) in the NYTimes:
Your Ancestors, Your Fate: ... my colleagues and I estimate that 50 to 60 percent of variation in overall status is determined by your lineage. The fortunes of high-status families inexorably fall, and those of low-status families rise, toward the average — what social scientists call “regression to the mean” — but the process can take 10 to 15 generations (300 to 450 years), much longer than most social scientists have estimated in the past.

We came to these conclusions after examining reams of data on surnames, a surprisingly strong indicator of social status, in eight countries — Chile, China, England, India, Japan, South Korea, Sweden and the United States — going back centuries. Across all of them, rare or distinctive surnames associated with elite families many generations ago are still disproportionately represented among today’s elites.

... Our findings suggest, however, that the compulsion to strive, the talent to prosper and the ability to overcome failure are strongly inherited. We can’t know for certain what the mechanism of that inheritance is, though we know that genetics plays a surprisingly strong role. Alternative explanations that are in vogue — cultural traits, family economic resources, social networks — don’t hold up to scrutiny.

... Our findings were replicated in Chile, India, Japan, South Korea and, surprisingly, China, which stands out as a demonstration of the resilience of status — even after a Communist revolution nearly unparalleled in its ferocity, class hatred and mass displacement.

... The notion of genetic transmission of “social competence” — some mysterious mix of drive and ability — may unsettle us. But studies of adoption, in some ways the most dramatic of social interventions, support this view. A number of studies of adopted children in the United States and Nordic countries show convincingly that their life chances are more strongly predicted from their biological parents than their adoptive families. In America, for example, the I.Q. of adopted children correlates with their adoptive parents’ when they are young, but the correlation is close to zero by adulthood. There is a low correlation between the incomes and educational attainment of adopted children and those of their adoptive parents.

These studies, along with studies of correlations across various types of siblings (identical twins, fraternal twins, half siblings) suggest that genetics is the main carrier of social status. ...  [ Italics mine ]
These results, and the original working paper in which they first appeared, were discussed in an earlier post:
While at UC Davis to give a colloquium earlier this week, I had the pleasure of meeting economic historian Greg Clark in person. Here's a sample of his latest work, which suggests that convergence of social classes has been surprisingly slow: averaged parent-child correlations of variables such as wealth, education and occupation are in the 0.7 -- 0.8 range over the last 200 years, the same as found in India, with its caste system! IIRC, Greg said he got the idea of using rare surnames from Nicholas Wade during an interview :-)
Correlations as high as 0.7 -- 0.8 are implausible from genetic factors alone without highly assortative mating. Traits such as height and IQ have narrow sense heritabilities as large as h2 ~ 0.6, so fraction of variance accounted for is ~ 60%, and midparent-child correlation as high as ~ 0.8, but under even somewhat random mating the parental midpoint is significantly closer to average than the phenotype of the more exceptional parent. This would cause children to regress to the mean much faster in height and IQ than in social status as indicated in Clark's data. It's also important to note that social status itself is only imperfectly correlated to observable phenotypes such as IQ, Conscientiousness or Extraversion. See Intergenerational mobility: Bowles, Gintis, Clark for more.

It seems likely that there is a social component which boosts the correlation due to genetic factors. This is not implausible (i.e., kids get a leg up in social status due to parenting or purely financial factors), but somewhat vitiates Clark's conclusion in the NYTimes essay above.


CalicoCat1 said...

Smarter people tend to be better looking, so that's likely one factor in success.

JayMan said...

It seems likely that there is a social component which boosts the
correlation due to genetic factors. This is not implausible (i.e., kids
get a leg up in social status due to parenting or purely financial
factors), but somewhat vitiates Clark's conclusion in the NYTimes essay

A more indirect effect of the genes, but an effect of the genes nonetheless?

chartreuse1737 said...

"...though we know that genetics plays a surprisingly strong role.
Alternative explanations that are in vogue — cultural traits, family
economic resources, social networks — don’t hold up to scrutiny..."

as if these were independent. a neapolitan in seoul would wind up in the loony bin. again there is the implicit assumption that intension and extension are the same thing. china an norway are and have been different environments selecting for different alleles just like the sahara and greenland are different enivironments. that there is such a thing as human societies does not imply that all societies are the same. this is an unknown known of the not so smart uber nerd clark (listen to him if you don't believe me).

steve hsu said...

But an adopted child could benefit from parenting or financial inheritance ...

chartreuse1737 said...

the british aristocracy is long lived and tall relative to commoners.

Bellcurve2 said...

As I understand, according to long term longitudinal study, nurture (including parenting) has no long term effect on the children's IQ and a number of other things. The longer the time after the children leaves the nest, the more their accomplishment reflect their underlying IQ. The effect of parenting on the accomplishment of the children by their 40s and 50s is probably little compared to to their accomplishment at age 18. However, assortative mating can have decisive effect on the following generation, which, as I understand, is probably this social component Steve writes about, leading to the 0.7-0.8 correlations.

For me, my parenting goal is for my children and future offsprings to be "happily and successfully assorted" in marriage and life. Parents may not be able to improve their children's own long term accomplishment. However, through "properly" tuned parenting and early tutelage in assortative mating and statistics, parents may be able to improve the average IQ and status of their grandchildren, though it is statistically extremely difficult to keep up over generations. The children's long term "fate" may be sealed by their IQ, through the genetic union of their parents, but parents can affect the IQ of their grandchildren through parenting, which I think should be one of the goal for parents with long term consideration.

Given the diminishing effect of such "enhanced" parenting after they leave home, with hopefully more wisdom and maturity, the grown children may have higher chance of marring a relatively more IQ and socially endowed spouse, if they marry "earlier" than "later" ("earlier", as in before or while their relative accomplishment trajectory peaks).

Please tell me this stands a chance of working, at least for a couple of generations. If not, I am all ears.

Hamish Johnston said...

Is it possible that when an unusual surname becomes associated with success, later generations benefit from the kudos. If you met a young Rockefeller today, you would be forgiven from assuming that person was destined for success. You may not make the same assumption of a young person called Ford or Walton.

Cornelius said...

averaged parent-child correlations of variables such as wealth,
education and occupation are in the 0.7 -- 0.8 range over the last 200
years, the same as found in India, with its caste system!

One way to get this result.
The West is meritocratic and merit is largely determined by genes, so children inherit the same abilities that made their parents wealthy/poor.
India provides few opportunities for meritocratic people of one caste to attain a higher status or for unremarkable members of another caste to lose their status.

One test would be to follow immigrants. If lower caste Indians are held back by society rather than genes, then you would expect them to reach the Western mean after immigration much quicker than those families who remain in India.
Another test would be to look at lower caste Indians who are able to attain some level of status by dint of hard work and/or intelligence. If Indian society - rather than genes - is responsible for holding back the Indian lower castes then we would expect the children of these successful individuals to revert to the mean quicker than in societies with less restrictions on social mobility.

I'll read the working paper to see if any of this is addressed.

Butch said...

Steve you may want to read this article on the caste system and IQ in India. Brahmins are supposedly another Ashkenazi jews...

When you go on their wiki page and go to the socioeconomic sections, they outperform even Ashkenazi jews

Magnusmaster said...

If success is written in our genes (hopefully not) we better get safe and reliable genome editing otherwise there's going to be genocide that would make hitler blush, either through embryo selection or gas chambers.

Hopefully some day we can change our genes as if they were our clothes. Maybe not possible but we can dream.

chartreuse1737 said...

"The West is meritocratic and merit is largely determined by genes"

is this satire?

chartreuse1737 said...

and what is success? as chomsky observed criticizing charles murray, there are a great many people for whom "success" is far from the top of their to do list.

Bellcurve2 said...

This reminds me of Steve's prior post on the movie Gattaca. There will always be a distribution curve for the phenotypic manifestation of any complex trait (such as IQ) involving multiple genes. Many probably use income as a surrogate marker for "success" and income (but not wealth) somewhat correlates with IQ. However, there is still a distribution curve for income for people with the "same" IQ. Even if everyone is genetically engineered to similar extent, there will always be a distribution curve for "success", however it is defined. It seems that "success" is relative. The top 20%, 5%, 1%, etc. will always be the minority. "Happiness", however, seems to be less dependent on income, after meeting a threshold.

Magnusmaster said...

Yes but can we truly talk about equality of opportunity or meritocracy if some people have higher IQ than others? Genetic engineering can level the playing field (it can also unlevel it even more, though).

chartreuse1737 said...

"As I understand,..."

that is a very incorrect paraphrase of the data. it may be that adoptive parents aren't very different from one another in the ways that make a difference. and there are examples like the polgar sisters where parenting made a difference in the "cognitive" phenotype.

chartreuse1737 said...

i'm sure clark has adjusted for that.

my y chromosome is also swiss from the canton for which switzerland is named no less.

stevesailer said...

Americans tend to nominate for President people with reassuring American-sounding names from the British Isles, or, at a stretch, the Netherlands. Obama, Dukakis, Goldwater, and Eisenhower are notable exceptions. This bias toward British, Irish, or Dutch names probably is strongest at the Presidential level these days (movie stars don't change their names as often anymore) but it has some impact.

Bellcurve2 said...

I suppose not. You do raise a good question and I appreciate that. I start to think of the implication of leveling the playing field. Since height and appearance (symmetry, BMI, etc.) all have genetic basis and do affect opportunity, I suppose those and all other traits that may affect opportunities and that likely involve multiple complex genes also need to be genetically engineered, if we are to level the playing field. I wonder what kind of society we will have if everyone has been genetically engineered to the same degree for predetermined occupation (scientist, football player, gymnast, sushi chef, CEO, banker, teacher, etc.). Who will decide the "specification" and "optimal combination"? How will that affect genetic diversity for the human race and its impact on unforeseen pathogens and threat? Is that a desirable society? Can someone think of a movie that explored this kind of society?

Iamexpert said...

Both income and wealth correlate with IQ.

Bellcurve2 said...

That's good to know. Thanks. Do you have a link for this?

chartreuse1737 said...

obviously they do, just not nearly as much as the social darwinists would like. and the effect of iq on income disappears once educational attainment is controlled for. that is, education mediates all of the advantage.

according to a study at the harvard ksg, at most 1/12 of intergenerational status transmission is due to the heritability of iq. and that's in racially heterogeneous america. so it's basically zero.

the notion that smart poor kids all become partners at gs is simply false. it was much closer to being true in the 50s in both britain and america than it is now.

Bellcurve2 said...

Is it feasible to beat regression to the mean in IQ in subsequent generation through assortative mating, just to keep average IQ at +2 to 3 SD range for each subsequent generation? I am not asking for +3-4 SD!! Let's say we start one person who is +2 SD and who comes from a family with average IQ of +2 SD. What kind of spouse does that person (and subsequent generation, on average) need to marry to keep the average IQ up? Steve wrote a lot about these a few years back but I can't figure this out myself since I am not +4 SD. I greatly appreciate anyone who can help me figure this out. If I am not phrasing the question correctly, I also appreciate your correction.

DeAndre Johnson said...

They also tend to hire people with reassuring "American" sounding names:

KarenJo12 said...

Until the 1960's in England the children of the working class were barred by actual formal enactments or informal structures from attending the schools necessary to qualify for membership in the elite clubs that controlled access to opportunities. The dimmest offspring of a duke went to Eton and then inherited boatloads of cash while the brightest offspring of coal miners --- dug more coal. Include the fact that Lord Nitwit got good and regular meals while living in a warm, dry, ventilated house, and got lots of outdoor exercise, while Coal Miner Jr. lived in a hovel and breathed coal dust all day, then of course by the time each was 16 His Lordship was better able to navigate life.

The fact that in the 21st century so many people want to believe that successful people deserve all their goodies because they're just better than the rest of us appalls me.

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