Tuesday, August 14, 2012

Some more observations about Ron Unz and IQ

There is an ongoing "debate" between  Richard Lynn and Ron Unz regarding international variations in IQ.  Although he is the publisher of "The American Conservative", Unz takes the classic Leftist view that  low IQ is caused by  poverty, although he does make the concession that "some residual European IQ differences might indeed be due to genetics rather than environment".  

Poverty is the cause of everything according to Leftists.  They even blamed the 9/11 events on poverty until it finally penetrated their unseeing eyes that Bin Laden was in fact a billionaire.

Unz's article is replete with accusations that Lynn has acted in bad faith  (though not in those  words), which seems to me rather deplorable, though I was not too surprised by it.  When Unz replied to my observations about crime and  immigration, his comments were almost hilariously "ad hominem":  He suggested that I was disqualified from commenting on such matters because I live in Australia!

Perhaps I can be rather Old Testament in the matter however by in turn accusing Unz of bad faith.  In his desire to discredit Lynn's  hypothesis of substantial genetic influence on IQ he cherrypicks his data heavily, as Sanders has pointed out at length.  And it also seems to me that he rushes by the German data in great haste.  I would think that the differences between the old East and West Germany should be a very good test of Unz's "poverty" hypothesis. After  several generations of real poverty, East Germans were found to have average IQs that were about the same as West Germans -- even though West Germany was one of the world's most prosperous countries, one which made a "miraculous" economic recovery from WWII  (the famous Wirtschaftswunder).

If poverty had no effect there, whence Unz's claim that poverty explains almost all IQ variation?  Unz does not allude to the German results in his latest article but here is what he said in his earlier article:
Consider, for example, the results from Germany obtained prior to its 1991 reunification. Lynn and Vanhanen present four separate IQ studies from the former West Germany, all quite sizable, which indicate mean IQs in the range 99–107, with the oldest 1970 sample providing the low end of that range. Meanwhile, a 1967 sample of East German children produced a score of just 90, while two later East German studies in 1978 and 1984 came in at 97–99, much closer to the West German numbers.

These results seem anomalous from the perspective of strong genetic determinism for IQ. To a very good approximation, East Germans and West Germans are genetically indistinguishable, and an IQ gap as wide as 17 points between the two groups seems inexplicable, while the recorded rise in East German scores of 7–9 points in just half a generation seems even more difficult to explain.

Unz here cherrypicks again by seizing on the widest possible gap in the data rather than on the reasonably inferrable average.  The 107 result is clearly an outlier and a West German mean of around 100 seems the best attested. And the convergence between the two later East German studies  suggest that the 1967 East German finding was also an outlier.  So we are left with an East German mean that is essentially undistinguishable from the West German  mean.

Will Unz be defeated by that fact?  Perhaps not. He leaves himself an "out" by saying "but East Germans hardly suffered from severe dietary deficiencies".  So now it is not poverty that affects IQ but rather "severe dietary deficiencies".  The goalposts have moved!

I don't know that it is really worth saying much more about Unz's merry journey through the data but I will briefly mention two other points:  Unz consistently discounts the immigrant effect, the claim that immigrants are in various ways a superior subset of their parent population.  Yet the USA seems a clear proof that such an effect exists.  Herrnstein & Murray long ago showed that lower IQ goes with lower social class and the mass of immigrants to both Australia and America in the past were clearly from the lower strata of their host societies. To this day, upper class English accents are as rare in Australia as British regional accents are common.  So average white IQs in both Australia and America should be lower than the average IQ in (say) Britain -- right? 

But it isn't so.  The average IQ in all three countries is essentially the same.  The most readily apparent explanation for that convergence would seem to be the immigrant effect:  The immigrants were a superior subset of the population from which they originated.  And the way America has in various ways led and dominated the world at least since WWII would also seem to suggest that those immigrant genes were pretty good.

A final point in defence of Lynn.  Unz says:  "Finally, Lynn closes his rebuttal by repeating his boilerplate disclaimer that he has “never maintained that IQ is overwhelmingly determined by genetics,” although this seems to be his clear reasoning in every single particular example he discusses"

I suspect here that Unz is failing to see that Lynn has had two aims in his work:  His main aim is to show that IQ is economically important and ascribing any origin to the  differences observed is secondary to that aim.  And that refusal to ascribe is what Lynn is doing when he makes modest claims for what he has shown.  In science, however, once one question is answered, new questions arise and Lynn's demonstration of national differences in IQ does quite immediately lead to a question of how those IQ differences arise.  And in rejecting Unz's "poverty" reasoning Lynn has moved on to the derivative question.

And even there, I think  Unz is seeing only what he wants to see in Lynn's words.  Lynn's denial of an "overwhelming" influence is perfectly consistent with around 100 years of IQ research.  The normal finding from twin studies is that IQ is about two thirds genetically determined.  Whether two thirds is "overwhelming", I leave others to judge but I submit that Unz has read more into Lynn's words than is there.

Prominent psychologist Steven Pinker also has some  comments on Unz's dubious logic and in addition  makes some useful points about the massive support for the heritability of IQ etc.  He is far too cautious to endorse Lynn's position, however.  To do so would be academic suicide  -- JR

Monday, August 6, 2012

Ron Unz and IQ

I seem to be a consistent critic of Ron Unz, editor of "The American Conservative". I noted yesterday (and earlier) that his idea of low criminality among Hispanics is contradicted by Obama's deportation  statistics and I also took a few potshots at his theory that IQ differences between nations are mostly the effect of environmental  factors. 

So I am pleased that Richard Lynn has now given a systematic reply to Unz on the IQ question.  Lynn echoes some of the points I made (and I did get an email from Lynn saying he liked my article) but his reply is far more detailed and scholarly and, I think, a good reply  to Unz's claims.

Unz has replied to Lynn and it looks to me that the two sides are converging, with the differences being in matters of degree. Both parties agree that the environment has some influence but Lynn makes a strong case for the importance  of genetics.


Could a brain scan tell you how smart you are? Research shows intelligence linked to strength of neural connections

More evidence that IQ is genetically determined.  We are now getting an idea of  the specific mechanisms involved

Research suggests that 10 per cent of individual differences in intelligence can be explained by the strength of neural pathways connecting the left lateral prefrontal cortex to the rest of the brain.

The findings, published in the Journal of Neuroscience, establish 'global brain connectivity' as a new approach for understanding how human intelligence relates to physiology.

'Our research shows that connectivity with a particular part of the prefrontal cortex can predict how intelligent someone is,' said Michael Cole, PhD, a postdoctoral research fellow in cognitive neuroscience at Washington University and lead author of the study.

He says the research is the first to provide compelling evidence that neural connections between the lateral prefrontal cortex and the rest of the brain make a unique and powerful contribution to the cognitive processing underlying human intelligence.

'This study suggests that part of what it means to be intelligent is having a lateral prefrontal cortex that does its job well; and part of what that means is that it can effectively communicate with the rest of the brain,' added study co-author Todd Braver, PhD, professor of psychology in Arts & Sciences and of neuroscience and radiology in the School of Medicine.

One possible explanation of the findings, the research team suggests, is that the lateral prefrontal region is a 'flexible hub' that uses its connectivity to monitor and influence other brain regions.

'There is evidence that the lateral prefrontal cortex is the brain region that "remembers" the goals and instructions that help you keep doing what is needed when you're working on a task,' said Prof Cole.  'So it makes sense that having this region communicating effectively with other regions (the "perceivers" and "doers" of the brain) would help you to accomplish tasks intelligently.'

While other regions of the brain make their own special contribution to cognitive processing, it is the lateral prefrontal cortex that helps coordinate these processes and maintain focus on the task at hand. This happens in much the same way that the conductor of a symphony monitors and tweaks the real-time performance of an orchestra.

The findings are based on an analysis of functional magnetic resonance (fMRI) brain images captured as study participants rested passively and also when they were engaged in a series of mentally challenging tasks associated with fluid intelligence, such as indicating whether a currently displayed image was the same as one displayed three images ago.

Previous findings relating lateral prefrontal cortex activity to challenging task performance were supported. Connectivity was then assessed while participants rested, and their performance on additional tests of fluid intelligence and cognitive control collected outside the brain scanner was associated with the estimated connectivity.

Results indicate that levels of global brain connectivity with a part of the left lateral prefrontal cortex serve as a strong predictor of both fluid intelligence and cognitive control abilities.

More  HERE