I’m impressed that you managed to get your sly accusations of fraud in again there though. Keep at it!

On reflection, if (and only if) you are deleting David Kane’s comment (7:58 pm), please delete my response (10:17 pm) as well. Not that his tripe deserves better, but I wouldn’t ask readers to take my word for that. Thanks.

I’d hazard a guess that twins in the studies tended to have far more similar social circumstances than a near-random ‘assignment’ to society would have.

Readers will soon find it hard to make sense of your comments since Henry will surely delete David Kane’s comment as soon as he sees it. More’s the pity because the soon-to-vanish comment is priceless. I hope Henry won’t object if I post a summary, although I recognise that doing so undermines the purpose of banning a troll.

David argues that since Cosma Shalizi respects James Flynn, and James Flynn respects Arthur Jensen, really it is (somehow) wrong that Cosma does not respect Arthur. Apparently there is a transitivity axiom at work here; I can’t quite make sense of it, since by induction it implies that Cosma should also respect known frauds like the late Sir Cyril Burt – which looks very like a reductio to me.

A further complaint is that Les Roberts, an epidemiologist who has devoted years of his life to studying mortality in hellholes like DR Congo and Iraq, in the hope of getting Western governments to do something about the dreadful conditions he has witnessed, wasn’t as helpful to his critic David Kane as David thinks he should be. Contrast that ungracious conduct with the exemplary behaviour of Arthur Jensen, who has devoted much of his life to demonstrating that African-Americans are an inferior breed on whose education public funds should not be wasted; Jensen was very helpful to Flynn, his critic. So clearly Jensen is a scholar and a gentleman and Roberts is neither.

I kid you not, folks. That’s what David Kane has to say. For those not in the know, David Kane has (without a scrap of evidence) accused Les Roberts and his colleagues of publishing a fraudulent study. I rather suspect Jensen’s attitude to Flynn would have been a bit less helpful if Flynn had behaved as Kane did. Another point of difference is that while Jensen can hardly dispute Flynn’s knowledge of psychology, Kane has shown himself unable to compute a crude mortality rate, even when the figures are supplied to him in a spreadsheet with the formula already entered. I wish I was joking but I’m not.

The Slate article also points out a recurring theme in these IQ stories, one that explains Cosma’s frustrations: I have heard hereditarians bring up the Minnesota twin study. It turns out that the study has serious design flaws that make the results hard to interpret. Hereditarians will never, ever state these flaws when they when they bring up the study. Here’s Slate:

Here is what you would never know about the Minnesota study from reading Jensen and Rushton, or, for that matter, Saletan. It held neither race nor expected IQ constant; the black children were adopted at a later age than the other children, which the study’s own authors note is associated with depressed IQ; the black children’s mothers had lower educational levels than those of the white children; the “quality of placement” for the white children was higher than for the other children; and as the study’s own authors have noted, the black and mixed-race children experienced severe adjustment problems as they grew up.

This is the behavior of a true scholar?

Thanks for your contribution here. And I’ll look forward to your future post on the topic with interest.

In closing, let me point out something that James Flynn wrote about Arthur Jensen.

I never suspected Arthur Jensen of racial bias. Over the years, I have found him scrupulous in terms of professional ethics. He has never denied me access to his unpublished data. His work stands as an example of what John Stuart Mill meant when he said that being challenged in a way that is “upsetting” is to be welcomed not discouraged. Before Jensen, the notion that all races were genetically equal for cognitive ability had become a dead “Sunday truth” for which we could give no good reasons. Today we are infinitely more informed about group differences. Equally important, the debates Jensen began are revolutionizing the theory of intelligence and our understanding of how genes and environment interact.

Why does that matter?

1) In puts into context Cosma’s insistence that most/all of those on the other side are “blithering idiots.” It was one thing to dismiss Rushton and Lynn as “charlatans.” It is another to attack someone like Jensen in the same way. (Cosma does not do this directly but everything he writes is consistent with my belief that he would put Jensen in the same category.) But, Cosma, on the one hand, clearly wants to believe that someone like Flynn does valuable/important/useful work, but Flynn has great things to say about Jensen (and also, I think, Rushton and Flynn). He doesn’t agree with all their views, but he relies on their data and considers them welcome members of the scholarly community. But how can he include Flynn within the tent while kicking out Jensen/Lynn/Rushton when Flynn would tell him that those three deserve admittance also?

2) And this all connects to Lancet. Really! My professional interests have little to do with race or IQ or g or Iraqi mortality. But I am a stickler for process, for scientists behaving the way that they ought to behave. Hate him or love him, but Jensen does so. (I understand that the same is true for Rushton and Lynn.) Contrast that with the behavior of Les Roberts who, to this day, refuses to share the household level data from L1 with anyone or that same data with some of his critics on L2.

Jensen shares his data with his fiercest and most intelligent critics. Roberts doesn’t. Only one of them is a real scholar. Can Henry or Daniel or Kieran tell the difference?

(Now is your chance to follow up the previous comment and admit you don’t believe institutional racism exists…)

Maybe it depends on whether you count the Irish as white? Most racist league tables put us a long way down the rankings.

Merely having the data is not enough – unless the actual number-crunching is done we can’t derive results. Was it done? I don’t know and, judging by the fact that you have no idea how many twin studies involve twins separated at birth, my guess is that you don’t know either.

All in all, you seem to have more interest in collecting ammunition to use against affirmative action than in evaluating this research on its merits. It’s not for me to advise you on how to wage that struggle, but FWIW your approach doesn’t make any sense to me. Even if it is ever established that low IQ is related to a genetic defect, that won’t affect the case for remedial action. Whether a disadvantaged group should be helped or not doesn’t depend on whether their handicap is traceable to their genes. Many people are crippled by diseases which have a genetic component, but I’ve never heard anyone using that as an argument against providing wheelchair ramps in public spaces.