14 December 2005

Daughter of Papalee, Sister of Minilee

They say the fruit never falls far from the tree.

Recently a letter Dr Lee Wei Ling wrote to the Straightened Times forum titled "Prestigious school not always the wisest choice", shows that credulity towards crackpot theories is indeed hereditary.

Like her sire, who believes in the superior glands of the Chinese race as the contributing factor to their dominance in Singapore, Dr Lee writes that
Our meritocratic system, and the fact that academic intelligence (some would call it IQ) is to a large extent genetically determined, has already allowed the cream to float to the top.

NO IT'S NOT.

On the heritability of IQ, Samuel Bowles and Herbert Gintis (2002), The Inheritance of Inequality, report after a meta-analysis of existing IQ research:
A person’s IQ — meaning, a test score — is a phenotypic trait, while the genes influencing IQ are the person's genotypic IQ. Heritability is the relationship between the two. Suppose that, for a given environment, a standard deviation difference in genotype is associated with a fraction h of a standard deviation difference in IQ. Then h^2 is the heritability of IQ. Estimates of h^2 are based on the degree of similarity of IQ among twins, siblings, cousins and others with differing degrees of genetic relatedness. The value cannot be higher than 1, and most recent estimates are substantially lower, possibly more like a half or less.

It is NOT a fact that intelligence is "to a large extent genetically determined". It is irresponsible and possibly a breach of ethics for Dr Lee to mislead readers so, and worse yet, fail to provide figures to illustrate (or rather disprove) the extent of genetically determined IQ.

It is also sheer incompetence and disconnection from reality that Dr Lee cheerfully advises academically outstanding students not to worry if they don't get into elite schools. After all, it's not as though the Old Girls/Boys Network actually exist. In Singapore, people succeed due to sheer intellect, not their connections and social capital!

8 comments:

Agagooga said...

Nono. Correlation of 1 means changes in IQ can be 100% predicted by looking at genes, 0.5 50% and 0 0%. No mention of causation, of course.

akikonomu said...

Have rewritten that paragraph.

Another way to explain it is:

A correlation of 1 means that IQ is solely explained by genetic inheritance...

Anonymous said...

Nowhere does she say that Chinese are superior for she never talks about race-IQ correlations. To put words into her mouth isn't very nice. Second, general intelligence is heritable. It just is. The question is rather whether IQ faithfully measures general intelligence. To which the most widely accepted answer is - only to a certain degree. And she does qualify her statement about the heritability of intelligence by saying "some would call it IQ". So, your talk about "crackpot theories" misses the point completely.

akikonomu said...

Nowhere do peer-reviewed studies say intelligence is largely inherited, which are her words, not mine.

Anonymous said...

Here is a random link to an extract from an article by Robert Plomin, a foremost authority on behavioural genetics:
http://info.med.yale.edu/chldstdy/plomdevelop/genetics/99jungen.htm
This one is partucularly telling:
"Genetic influence on g is not only statistically significant, it is also substantial, especially when compared to other research in the behavioral sciences that rarely explains 5% of the variance."
That the dominant ideology in humanities and social sciences prefers not to notice such things and to subscribe to a ridiculously outmoded radical empiricism doesn't mean we should blind ourselves and pretend they don't exist.

Anonymous said...

Something was wrong with the shortcut. Here it is again:
http://info.med.yale.edu/chldstdy/
plomdevelop/genetics/99jungen.htm

akikonomu said...

Firstly: Robert Plomin is a expert in behavioural genetics. IQ - whether defined by political overlord types, scientist types, or even those humanities types - is a phenotype, not a behaviour.

Stephen Jay Gould on "g" and its related measures, in The Mismeasure of Man:

Herrnstein and Murray's correlation coefficients are generally low enough by themselves to inspire lack of confidence. (Correlation coefficients measure the strength of linear relationships between variables; the positive values from 0.0 for no relationship to 1.0 for perfect linear relationship.) Although low figures are not atypical for large social–science surveys involving many variables, most of Herrnstein and Murray's correlations are very weak—often in the 0.2 to 0.4 range. Now, 0.4 may sound respectably strong, but—and this is the key point—R2 is the square of the correlation coefficient, and the square of a number between zero and one is less than the number itself, so a 0.4 correlation yields an R–squared of only .16. In Appendix 4, then, one discovers that the vast majority of the conventional measures of R2, excluded from the main body of the text, are less than 0.1

I don't appreciate your raising up of a humanities type radical strawman. Perhaps you should tell me what's so radical and outmoded about studying IQ in relation to: parental behaviour, social class, social capital? At least the radical humanities type have a clear transmission mechanism for their variables and IQ...

akikonomu said...

Robert Plomin is first and foremost a behavioural psychologist. So were the authors of The Bell Curve, Papalee's favourite bedtime book. That is to say, all the genetics/IQ experts that matter are humanities type. So your bombthrowing is a little futile.

Secondly, the American Psychological Association's task force, in order to defend the findings of The Bell Curve, chose to emphasise environmental over genetic factors. Stinging mark of confidence that is.