Friday, April 14, 2017

More on politics and IQ

Further to my recent comments on IQ, someone has drawn my attention to a 2014 article by Noah Carl.  Carl recently came to attention for his articles on Leftism among academics. I had some comments on that on March 5 and on March 17.  Carl is clearly something of a bad boy from a Leftist perspective.  The 2014 journal article is as follows:

Cognitive ability and party identity in the United States (2014)

Noah Carl


Carl (2014) analysed data from the U.S. General Social Survey (GSS), and found that individuals who identify as Republican have slightly higher verbal intelligence than those who identify as Democrat. An important qualification was that the measure of verbal intelligence used was relatively crude, namely a 10-word vocabulary test. This study examines three other measures of cognitive ability from the GSS: a test of probability knowledge, a test of verbal reasoning, and an assessment by the interviewer of how well the respondent understood the survey questions. In all three cases, individuals who identify as Republican score slightly higher than those who identify as Democrat; the unadjusted differences are 1-3 IQ points, 2-4 IQ points and 2-3 IQ points, respectively. Path analyses indicate that the associations between cognitive ability and party identity are largely but not totally accounted for by socio-economic position: individuals with higher cognitive ability tend to have better socio-economic positions, and individuals with better socio-economic positions are more likely to identify as Republican. These results are consistent with Carl's (2014) hypothesis that higher intelligence among classically liberal Republicans compensates for lower intelligence among socially conservative Republicans.


So what are we to make of it?  Let us first compare it with two papers by the indefatigable Ian Deary.  Deary has access to some very well sampled British databases so is in a position to report highly generalizable results:


Childhood intelligence predicts voter turnout, voting preferences, and political involvement in adulthood: The 1970 British Cohort Study (2008)

Ian J. Deary


Little is known about the association between measured intelligence and how people participate in democratic processes. In the 1970 British Cohort Study, we examined the association between childhood intelligence and, at age 34: whether and how people voted in the 2001 UK general election; how they intended to vote; and whether they had taken part in other political activities. People with higher childhood intelligence were more likely to vote in the 2001 election (38% increased prevalence per SD increase in intelligence), and were more likely to vote for the Green Party and the Liberal Democrats (49% and 47% increased prevalence per SD increase in intelligence, respectively). The intelligence-Green party voting association was largely accounted for by occupational social class, the intelligence-Liberal Democrat voting association was not. Similar associations between intelligence and preference for the Green Party or Liberal Democrats were found as regards voting intentions, but neither of these associations was accounted for by occupational social class. People with higher childhood intelligence were more likely to take part in rallies and demonstrations, and to sign petitions, and expressed a greater interest in politics (40%, 65%, 33%, and 58% increased prevalence per SD increase in intelligence, respectively).



Bright Children Become Enlightened Adults (2008)

Ian J. Deary


We examined the prospective association between general intelligence (g) at age 10 and liberal and antitraditional social attitudes at age 30 in a large (N = 7,070), representative sample of the British population born in 1970. Statistical analyses identified a general latent trait underlying attitudes that are antiracist, proworking women, socially liberal, and trusting in the democratic political system. There was a strong association between higher g at age 10 and more liberal and antitraditional attitudes at age 30; this association was mediated partly via educational qualifications, but not at all via occupational social class. Very similar results were obtained for men and women. People in less professional occupations-and whose parents had been in less professional occupations-were less trusting of the democratic political system. This study confirms social attitudes as a major, novel field of adult human activity that is related to childhood intelligence differences.



So in the first Deary study above we find that high IQ British voters did lean Left but they leant towards minority Leftist parties, not the major Leftist party, the Labour party.  The Labour party has some repellent union associations so may have been seen as unattractive for that reason.  The two minor parties, however, come across as high-minded.

The second study looked at the correlates of attitudes rather than vote.  And ever since LaPiere in the 1930s we have known that attitudes are at best only weakly related to behaviour.  Deary found greater social liberalism among high IQ people.

And so we come to Carl's 2014 American study. GOP identifiers were found to be slightly brighter on average than Democrat identifiers.

It is of course perfectly possible and reasonable that trends in Britain might not be reflected in the USA -- and vice versa.  That would seem to be the case here. But note that in no case is the major Leftist party favoured. But the association between vote and IQ was in any case weak so IQ is clearly a very minor factor in determining vote.  As I have often argued, it is a miserable personality that makes you Leftist.  See, for instance,  here

Thursday, April 6, 2017

Politics and IQ

Are smart people Left-leaning?  There is some recent evidence to say so, though the correlation is weak.  A paper by Michael Woodley is therefore of interest ("Problematic constructs and cultural-mediation: A comment on Heaven, Ciarrochi and Leeson (2011)").

He surveys the literature and shows that the findings go both ways.  On some occasions Leftists score highest while on others conservatives do. 

He resolves that the way I do -- by saying that high IQ people are quicker to figure out what is currently socially acceptable and say that.  At the moment being conservative is likely to bring a ton of abuse ("racist") down on your head so it is no wonder that smart people claim to be Leftist

Monday, April 3, 2017

Scientists predict reading ability from DNA alone

Reading ability is a major component of IQ so this is another step forward towards measuring IQ directly from brain features

Researchers from King's College London have used a genetic scoring technique to predict reading performance throughout school years from DNA alone.

The study, published today in Scientific Studies of Reading, shows that a genetic score comprising around 20,000 of DNA variants explains five per cent of the differences between children's reading performance. Students with the highest and lowest genetic scores differed by a whole two years in their reading performance.

These findings highlight the potential of using genetic scores to predict strengths and weaknesses in children's learning abilities. According to the study authors, these scores could one day be used to identify and tackle reading difficulties early, rather than waiting until children develop these problems at school.

The researchers calculated genetic scores (also called polygenic scores*) for educational achievement in 5,825 individuals from the Twins Early Development Study (TEDS) based on genetic variants identified to be important for educational attainment. They then mapped these scores against reading ability between the ages of seven and 14.

Genetic scores were found to explain up to five per cent of the differences between children in their reading ability. This association remained significant even after accounting for cognitive ability and family socio-economic status.

The study authors note that although five per cent may seem a relatively small amount, this is substantial compared to other results related to reading. For example, gender differences have been found to explain less than one per cent of the differences between children in reading ability.

Saskia Selzam, first author of the study from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King's College London, said: 'The value of polygenic scores is that they make it possible to predict genetic risk and resilience at the level of the individual. This is different to twin studies, which tell us about the overall genetic influence within a large population of people.'

'We think this study provides an important starting point for exploring genetic differences in reading ability, using polygenic scoring. For instance, these scores could enable research on resilience to developing reading difficulties and how children respond individually to different interventions.'

Professor Robert Plomin, senior author from the IoPPN at King's College London, said: 'We hope these findings will contribute to better policy decisions that recognise and respect genetically driven differences between children in their reading ability.'

*Calculating an individual's polygenic score requires information from a genome-wide association study (GWAS) that finds specific genetic variants linked to particular traits, in this case educational attainment. Some of these genetic variants, known as single nucleotide polymorphisms (SNPs), are more strongly associated with the trait, and some are less strongly associated. In a polygenic score, the effects of these SNPs are weighed by the strength of association and then summed to a score, so that people with many SNPs related to academic achievement will have a higher polygenic score and higher academic achievement, whereas people with fewer associated SNPs will have a lower score and lower levels of academic achievement.