Haven’t had a grouchy GWAS thread from me in some time, but this GWAS of occupational status punches my buttons. biorxiv.org/content/10.110…
I don’t have a lot nice to say, so I should be clear that none of this really pertains to these particular authors. The issues that I have are with industry-standard practices. /2
Sep 9, 2022 • 7 tweets • 2 min read
I am teaching the grad psychopathology seminar, and despite everything I still insist on spending the first week talking about Freud and psychoanalysis with a group of very smart and very skeptical young people. Here is what I tell them. No claim of originality. /1
If a significant part of what we call mental illness consists of "problems in living," what is the nature of those problems? Why, in a world in which we are so lucky to be alive and have so many possibilities for joy, do we spend our time worried at best, miserable at worst? /2
Aug 29, 2022 • 8 tweets • 3 min read
A thought on the @NatureHumBehav. ALL journals have a policy like this, it's just that most of them don't write it down. The idea that journals should publish everything that is scientifically valid is a fantasy. Real journal articles don't arrive labelled valid or invalid. /1
I don't mean that in some high-falutin' "science always exists in a cultural context" sort of way. I mean it from the point of view of a working Associate Editor. Peer review helps but doesn't solve the problem. You can find three reviewers to approve or trash anything. /2
May 17, 2022 • 11 tweets • 3 min read
Still thinking about Peter Visscher's essay and reply. The last point in his reply accuses GWAS skeptics of moving goalposts. This takes some chutzpah on the part of the GWAS community. A thread: /1
You may be able to accuse someone of moving goalposts, but not me. I was kicking field goals on this subject in 1998, when GWAS was a twinkle in human genetics' eye. /2
May 16, 2022 • 12 tweets • 3 min read
Peter Visscher left a comment on my blogpost from last week, here: turkheimer.com/peter-visscher…. First things first, I got the journal where he published his article wrong. I fixed it. /1
Visscher doesn't like that I used the word "eugenic" in connection with his essay. But, broadly, eugenics refers to the use of genetics to explain existing racial, social and economic disparities. Uncritical application of between family GWAS does just that. /2
Mar 31, 2022 • 9 tweets • 3 min read
So EA4 is finally out. It's a massive project, and I am not here to question its scientific validity, but rather to ask a tougher question: Has GWAS of complex human behavior turned out to be a disappointment? /1 nature.com/articles/s4158…
We are now over 3 million participants. A 3x increase in sample size produced a 25% increase in between-family R2. Remember when we were told that bigger samples would inevitably lead to scientifically or practically actionable results? Are we still waiting for that? /2
Nov 10, 2021 • 11 tweets • 3 min read
Yesterday @kph3k noted that I "loathe" decile analysis as a way of describing the results of a PGS analysis. The subsequent discussion clarified why I loathe it-- it's a misleading way of reporting results, a systematic sleight of hand to disguise the import of a small effect. /1
To illustrate, I created some simple data for 10,000 observations. PGS has a mean of 0 and a SD of 1; IQ has a mean of 100 and a standard deviation of 15. They are correlated around .205, so the PGS accounts for about 5% of the variance in IQ. /2
Nov 1, 2021 • 10 tweets • 3 min read
From time to time you hear it said that executive function, a cognitive ability involving mental control, is 100% heritable. It seems like a compelling basis for hereditarianism- under all that complexity there is a solid gold nugget of pure genetic variation! [wonky thread]
The @kph3k book, for example, says "First,it is nearly 100 percent heritable. That is, within a group of children who are all in school, nearly all of the differences in general EF between them are estimated to be due to the genetic differences between them." /2
Oct 16, 2021 • 5 tweets • 1 min read
When I find myself besieged by the kind of people in my mentions this morning, it is tempting to be goaded into sounding as though I think genetic endowment places 0 limits on people, or that GWAS has made no meaningful contributions to science, or that the modest predictions /1
of behavioral PGS are completely useless. I don't think any of those things and I never have. I am, after all, a working empirical behavior geneticist. What I do think is that the hardcore genetic world the right is forever envisioning shows no signs of becoming reality. /2
Sep 14, 2021 • 5 tweets • 2 min read
Great thread from @molly_przew. I have been pushing back against the notion that there can be separate causal processes operating within and between groups for a long time. /1 academia.edu/download/50309….
On a superficial read, you might think this argument would give comfort to the "race difference" people who argue that individual level heritability implies a genetic basis for group differences. (The only time I ever met Arthur Jensen he said he liked the paper above.) /2
Apr 24, 2021 • 8 tweets • 2 min read
1/ Arguing with myself: I say that "race science" is meaningless because it assigns causal value to heritability coefficients whose causal implications are not understood and generally exaggerated.
2/ But by impugning the motives of the race scientists, aren't I shutting down the very research that might produce that knowledge? No. Let's say you believe that Group X carries a gene or some polygenic mechanism that makes them exceptionally good violin players.
Apr 23, 2021 • 6 tweets • 2 min read
98% of "race science" consists of nothing but this: 1) Trait X is heritable in individuals; 2) heritability means genes have "something to do" with the trait; 3) Groups differ on the trait; 4) Genes have "something to do" with the group difference. This is underdetermined BS. /1
The first law of BG offers an obvious reductio of the argument. All individual differences are heritable, groups differ on all sorts of things. So if all you want is a vague assertion that genes have "something to do" with all human differences, OK. /2
Feb 21, 2021 • 8 tweets • 3 min read
This study, by @mendel_random@timfrayling and others, shows that participation in various parts of the UK biobank depends in complex ways on genotype. You can imagine what I think-- the authors take a steadfastly optimistic tone- we can use this to control for bias! /1
Whereas I see it as the bubbles slowly rising to the surface as the GWAS-of-behavior project disappears under the surface of the gloomy prospect. But that isn't what I want to say here-- instead I want to be very old-fashioned. /2
Jul 11, 2020 • 9 tweets • 2 min read
1. I am grateful for this reply because it makes clear what is at stake. The hereditarian hypothesis is that a portion of the disadvantage faced by Black people is not the result of discrimination, but instead of their own innate characteristics.
2. Apparently the upside of this hypothesis is that it allows White people to feel better about the current “destructive and divisive culture war.”
Jul 8, 2020 • 9 tweets • 2 min read
Some thoughts on the Harpers letter. I support it in spirit: the world would be a better place if people could be more tolerant and open minded. But I think their argument is oversimplified to make the problem seem easier than it really is. /1
Cancellation is not new. Consider holocaust deniers. If the chairman of your history department announces that the Holocaust never happened, she is going to be canceled, and this was true long before Twitter. Why, exactly? /2
Feb 5, 2020 • 6 tweets • 2 min read
In the course of my usual complaining about a GWAS-- never mind-- it occurred to me that the core of my problem is the lack of an appropriate null model. /1
Usually when one conducts a study, there is a possible null result that will lead you to say, "Oh well, it didn't work." In a well-functioning scientific world that result is still publishable. What would such a result look like for GWAS? /2
Mar 31, 2018 • 5 tweets • 2 min read
I can only say this so many times: *of course* IQ is heritable in the statistical sense. No one who knows me or my work could possibly think I need this explained to me. We said so in the first paragraph of our original piece. /1 goo.gl/SZpKhx @kph3f @ezraklein
But the general heritability of IQ has 0 implications for the causes of a particular group difference. I get it that saying, maybe the group difference is *partly* genetic seems like a moderate stance on a polarized topic, but that is an illusion. /2
