IQ, Race, Poverty, Violence . . . The Body Needs a Head

Smart Fraction _ La Griffe du Lion
One might not be impressed by the difference in average IQ between European (avg. IQ = 100) and African-American populations (average IQ = 85). But if one looks at the implications of that simple and consistent difference -- at the extreme right tail of the distribution curve -- one begins to understand the potency of the so-called "smart fraction."

The smart fraction of a larger population has a great deal to do with the overall prosperity and technological sophistication of the society at large. In fact, a sufficiently large smart fraction can move a society well above the GDP which one might predict based upon the average IQ.

GNXP blogger Razib Khan considers the implications of a difference in means on the "smart fraction" as small as 5. In terms of awards, achievements, accomplishments, and distinctions, the difference can be quite significance, assuming a normal distribution and comparable standard deviations in the two groups.

Two populations may have a large overlap and differ only slightly in their means. Still, the most outstanding individuals will tend to come from the population with the higher mean. The implication, I think, is clear: whenever an institution or society singles out individuals who are exceptional or outstanding in some way, racial differences will become more apparent. That fact may be uncomfortable, but there is no way around it.
The fact that racial differences exist does not, of course, explain their origin. The cause of the observed differences may be genetic. But it may also be environmental, the result of diet, or family structure, or schooling, or any number of other possible biological and social factors.
My conclusion, to repeat, is that whenever a society singles out individuals who are outstanding or unusual in any way, the statistical contrast between means and extremes comes to the fore. I think that recognizing this can eventually only help politicians and social policymakers.
_quoting the eminent geneticist James F. Crowe, author of Unequal by nature: a geneticist’s perspective on human differences

Imagine the following trait with two distributions (i.e., two populations):
- Mean = 100 and 105 (average value)
- Standard deviation = 15 (measure of dispersion)
- Let’s assume a normal distribution
Let’s plot the two distributions:

Observe the close overlap between the two distributions. Most of the variance occurs within both sets of populations. Now let’s impose a cut-off of about ~130 on the curves:

Now the similarity between the two curves is not as striking. As you move to the tails of the distribution they begin to diverge. In other words, the average of the two populations is pretty much interchangeable, but the values at the tails differ. Now let’s move the cut-off to 145:

The difference is now even more stark. Let’s compare the ratios of the area under the curve for the two populations as defined by the cut-offs:
Value at 100 = 1.26 (any given individual in the blue population is 1.26 times more likely to be above 100 than in the red population)
Value at 130 = 1.83
Value at 145 = 28
What does this entail concretely? As Crow noted above if you sample from the tails of the distribution then very modest differences between groups become rather salient...
_Razib_Khan_in_Discover

What is true for IQ and achievement also seems to be true for poverty, violence, and other socioeconomic tendency which appear to be mediated in large part genetically.

When one looks at African and African-derived populations around the world, one is struck by the high levels of violence, the high and persistent prevalence of poverty, and the low levels of achievement in terms of technological and scientific invention, and general scholarship.

Even without average IQ scores of various nations, it would be possible to rank them in terms of violence, per capita GDP, and achievement in various fields such as science, technology, and scholarship. One could use those rankings to approximate national average IQ -- keeping in mind a number of caveats including various governmental limitations on private economic activity.

As shown by La Griffe du Lion, a large smart fraction -- such as the Chinese in Indonesia or non-Africans in South Africa -- can push a country to perform well above the level which might have been predicted based upon average national population IQ, in terms of GDP, research, and academic achievement. But the high levels of violence in South Africa cannot be obscured by its smart fraction, revealing one of the limitations of the "bootstrap" approach to helping low IQ societies.

Low IQ societies can be assisted by high IQ sub-populations to a significant degree. But if the population average IQ is too low, there are limits to the benefits which the entire society can enjoy from the achievements of a high-IQ fraction. In other words, such a society might enjoy advanced communications and computational networks, abundant and reliable electrical power, and a generally healthy economy. But unless a way is found to raise the IQs of the low IQ population majority, pockets of crime, corruption, and violence will persist.

What about advanced societies possessing appreciable minorities that display traits of high violence, persistent inter-generational poverty, and low IQ? Economically and in terms of achievement, such nations can do rather well in comparison to most other countries. But if the sub-populations displaying high crime, high poverty, and low achievement are increasing in numbers faster than their higher achieving countrymen, the long term prospects for such societies might not be so bright.

This is a situation faced by a number of advanced nations, located on multiple continents of the world. The situation is being ignored for reasons of political correctness, but the underlying reality and its inevitable fallout cannot be suppressed indefinitely.

Other than stressing the importance of treating all population groups equally under the law, there is no clear solution to the impending problem. It would be nice if IQ gaps could be narrowed, while at the same time increasing IQ overall for all groups. But as long as political correctness leads to the suppression of exactly the kind of research which might lead to such remedies, society is figuratively shooting itself in the head.

A few articles for background reading:

Race Difference in Intelligence Over Millenia

Brain Volumes and IQ in Children

Don't Count on the Flynn Effect

Black White Difference in IQ and Grades.... This study is interesting for trying to find an explanatory reason for the difference in scores, based upon another set of psychological measurements. It appears to be a good example of psychological inbreeding and self-blinding.

Links Between Information Processing Speed, Working Memory, and IQ... The abstract is at the link, and the full 18 MB dissertation is available to University of Queensland staff and students.

Clearly this issue spans many scholarly fields of human endeavour, from genetics to statistics to psychology to economics to philosophy to sociology to neuroscience, and more. Very few can master all fields of study, and any complex line of reasoning necessarily involves a number of assumptions which can be challenged.

But this particular area of study is particularly dangerous for students and scholars, given the political overtones involved. Be very careful how you discuss these issues, and be particular with whom you discuss these topics. Despite the over-riding importance of these questions to advanced societies, over time, no matter how good your intentions, if you open your mouth at the wrong time, you can burn a large number of career bridges.

Hope for the best. Prepare for the worst.