Saturday, September 24, 2005

Intelligence and Wealth of Nations

The last post (Men are Smarter) caused a spirited interchange at Starbucks this morning and a few terse blog comments (You’re stupid!!!) all thoroughly appreciated. The conversation raised several interesting questions about IQ.

From Wikipedia, an intelligence quotient or IQ is a score derived from a set of standardized tests that measure a person's cognitive abilities, ie intelligence. IQ scores are correlated with measures of brain structure and function as well as size. IQ tests measure actual performance, not innate potential. Among the developed countries, IQ is highly heritable, and by adulthood the influence of environment on IQ is undetectable.

For a given group, IQ scores are generally normalized such that the average is 100 and the standard deviation is 15. The distribution is Gaussian (bell shaped) and 68% of the scores fall within +/- 1 standard deviation, i.e. between 85 and 115. IQ is strongly correlated with academic success, and well correlated with job performance and advancement, health, longevity, and literacy. IQ and happiness are not correlated.

When comparing different groups, say men and women, one must not normalize the distributions, since it’s the average score for each group that is most interesting. Thus the Irwing/Lynn study showed that the mean IQ of the men is 5 points higher than the mean IQ of the women in their sample of 100,000 people.

Prof. Richard Lynn showed in a separate study that national per capita incomes and rates of economic growth are positively correlated with national IQ. He found that national IQ explains 57 percent of the variance of real GDP per capita.


Lynn studied 60 of the largest nations having national mean IQs ranging from 62 (Ghana) to 110 (Japan) and with 1998 GDP/person ranging from $458 (Sierra Leone) to $29,605 (United States). Some of the mean IQs include Canada-97, China-98, France-97, Germany-103, India-82, Israel-90, Italy-103, Mexico-88, Russia-96, the UK-100 and the USA-98.

Taking the countries in three groups of 20, the data look like this:

Group ------- IQ Range --- GDP/person

Top 1/3 ------ (97-110) --- $20K
Middle 1/3 --- (85-96) ---- $9K
Lowest 1/3 --- (62-84) ---- $3K

The correlation of wealth with IQ is obvious. There are other secondary factors including whether countries operate free market or socialist economies and unique circumstances such as the possession of valuable natural resources like oil in the case of Qatar (IQ-78, GDP/P-$21K) and trade sanctions imposed on Iraq (IQ-87, GDP/P-$4K).

However, if we look at Western Europe compared to the USA we find a large discrepancy in GDP/person that cannot be explained by IQs, markets or resources. For comparable IQs in the range 97–103, the USA GDP/person is 50% higher than the European’s. To my mind that huge difference is explained by the lower tax rates and governmental regulations and the higher work ethic and level of entrepreneurship “in this, the greatest country on God’s green earth.”

4 Comments:

Anonymous Anonymous said...

"the USA GDP/person is 50% higher than the European’s."

Are you suggesting that Socialism is counterproductive???
My oh my!!! (Hee hee heh heh heh)

Keep up the fine work, Bill!

David

11:58 AM  
Anonymous Anonymous said...

I am never bored when I read your writings. LOL!!!!

I just love to needle you. Who else on this planet tells you that you are boring?

Jill

3:35 PM  
Anonymous Pamela said...

YooHooo!! Did ya'll notice Italy has the highest average IQ? 103!
Hmm, Billy Lama...good ole Italian boy from some mighty good stock! Capisce?
Intelligente!!
Bravisimo, Billy! Once again an eccellente blogo! E Salute!

4:29 PM  
Anonymous Anonymous said...

Per our conversation about g, Spearmand viewed it as principally being related to the ability to perform intellectual operations he called “eduction of relations and correlate”. The eduction of relations, he wrote, was when a person has in mind any two or more ideas he has more or less power to bring to mind any relations that hold between them. Similarly, the eduction of correlates is when a person has in mind any idea together with a relation, (s)he has more or less power to bring up into mind the correlative idea.

One of the problems with your analysis is the issue of the “continuum of reproductive casualty”.

Populations from different countries may demonstrate lower IQs because they are poor and as such are less able to provide the type of environmental support necessary to optimize the expression of the genotype.

“The relationship between certain biological variables and intelligence is indirect and is related to the fact that individuals with different social status may have different genotypes and may also provide different cognitive socialization experiences for their children. …one reason that there may be differences in intelligence between groups with different social status is that these groups differ in the probability of providing optimal biological environments during pregnancy.” (Brody and Brody, 1976).

A related problem is the covariance of genetics and environment

I also refer you to The Geography of Thought, by Richard Nisbett, 2003 and his discussion of how different cultures emphasize different kinds of problem solving strategies in their youth which then manifest as different performances on IQ tests.

Where were the cheese-eating surrender-monkies?

David

2:10 PM  

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