Another Look at Average: What Can You Do with Honorable Men at 85?

This may read like a discussion about age. But it is not. Rather, it is one about intelligence. The validity of psychometrics is strongly established. However, IQ score with its confounders could show an interesting meaning with subtle deviation from what we have come to know. Although IQ scores should be largely statistical, we could, perhaps, learn something by looking at data from an interesting study in India.

Psychologist Arthur Jensen, in his book, Straight Talk About Mental Tests, showed that there are four socially sensitive thresholds on the IQ scale that mark major divisions in the probabilities of educational achievement, which may have important consequences in a person's life. He added that these thresholds are a result of the educational and occupational structure of modern industrial societies and the demands they make on the kind of mental ability measured by IQ tests. Professor Jensen explained:

The four socially and personally most important thresholds on the IQ scale are those that differentiate with high probability between persons who, because of their level of general mental ability, (1) can or cannot attend a regular school (threshold at about IQ 50), (2) can or cannot master the traditional subject matter of elementary school (about IQ 75), (3) can or cannot succeed in the academic or college preparatory curriculum through high school with good enough grades for college admission (about IQ 105), and (4) can or cannot graduate from an accredited four-year college with grades that would qualify for admission to a professional or graduate school (about IQ 115).

None of these thresholds is inexorable. They merely indicate the IQ level below which the probability is very slight that the particular achievement will be realized (emphases mine).

A study was done at an Indian medical college to know the duration of preparation, self-study hours, academic performance and its association with the IQ level of medical students, to state how to shorten the duration of completing MBBS degree.

A cross-sectional study was done on 300 medical students using a structured questionnaire derived from IQtest.com. Data collection and appropriate statistical test were applied considering p-value ≤ 0.05 as significant.

Yes, I know that online IQ tests have a bad reputation and tend to score inflation and poor validity. But the test in question did not appear to inflate the scores as we will see. And on the structure of the test, this Intelligence Test contained 38 questions and utilized 13 intelligence scales: arithmetic, algebraic, rote utilization, logical, visual apprehension, spatial skill, intuition, general knowledge, vocabulary, short term memory, spelling, geometric, and computational speed. So it may be reasonable to expect this test to give at least a crude measure of intelligence in the cohort, and to roughly rank its members.

Bring in the Results

On application of IQtest.com 5 (1.7%) subjects had below average IQ, 150 (50%) subjects had average IQ and only 30 (10%) had gifted/genius/extraordinary IQ. The academic performance of students with average IQ was highest and that of below average IQ was poorest among all. The academic performance had no positive or negative correlation with the IQ level of students (Table 3).

Most of the students had IQ in between 85 to 129 i.e. average and above average IQ.

All the students with higher IQ (gifted/genius/extraordinary) spent less than six hours for study and rest of the time in sports and extra-curricular activities.

But what is more interesting is how the performance of the average (85-114) and above average (115-129) IQ students compare.

Among 115 students with above average IQ, 37 (32.2%) spent less than six hours and 78(67.8%) more than six hours for their studies per day. Among students with average IQ 54 (36%) spent less than 6 hrs and 96 (64%) more than six hrs for their study (Table 5). The percentages are similar for both groups.

Among students with above average IQ, 73.9% needed 1 year for medical entrance exam preparation while 52% of average IQ students did. 20.9% needed 2 years among students with above average IQ while it was 28% for average IQ students (Table 4). There are overlaps of about 70% each in both durations for both groups!

94.8% of above average IQ students needed at most 2 years for preparation while it was 80% for average IQ students.

The academic performance of students with average IQ was highest (Table 3) in this study (of course, this could change in another study), showing the presence of both motivation and capacity.

Apparently, we have much to do with honorable men and women at 85, perhaps contrary to what the literature would suggest. They are medical doctors in our midst, proudly!

I would want to see more similar studies. But hardly was this performance pattern a fluke considering the sample size.

An Attempt to Reconcile the Group Differences in IQ - Part 2

Earlier in October 2017, I had made an attempt to reconcile the observed group differences in IQ scores. This article is a sequel, albeit a short one, that aims to propose a working mechanism for the biological marker k, that was proposed to be responsible for the differences. This article follows the critical reasoning and inductions of its prequel.

Everything is different, but the same

Another new paper finds that the GWAS hits for IQ – largely determined in Europeans – don’t work in people of African descent. That was always a possibility: I’ve talked about it. If you look at the frequencies of height alleles (determined from GWAS in Europeans) you would predict that Pygmies are pretty short – but they’re considerably shorter than that. They have their own private alleles influencing height, which make them even shorter than you would think. Or, if you tried to estimate skin color in Koreans by the frequencies of variants that cause light skin in Europeans, you would conclude that they were black as night – but they’re not. They’re pretty light-skinned, but that’s caused by light-skin alleles common in East Asia, almost completely disjoint from the common light-skin alleles in Europeans.

So you can’t use those GWAS hits to tell how smart sub-Saharan Africans are, at least not today. All you can use are IQ measurements and achievements. It is as if the only way we could determine your height was by using a ruler, instead of GWAS predictions.

- Gregory Cochran, on his blog post.

A light that is getting brighter?

The paper that was mentioned is titled, Heterogeneity in polygenic scores for common human traits. Appropriately titled, the paper suggests differences in trait architecture between groups. And we can reasonably expect architectures to have projections.

The paper had stated that "PGSs created using weights derived from GWAS performed in individuals with European Ancestry generally do not perform as well in individuals with African Ancestry". So different groups have different trait architectures.

We may safely assume that an IQ score is a projection of the intelligence trait. If we are correct, scores within a group may be projections of their trait architecture for intelligence. 

Why so? What really is intelligence? Commenting on this, Patrick Meredith, professor of psychophysics at Leeds University, England, said: "It might be held that Frenchmen are brighter than pygmies, but if you see pygmies in their natural environment making bridges out of fibre and living life successfully you might ask what you mean by intelligence. . .". It may be that a pygmy has a different intelligence trait architecture from a Frenchman's, hence his lower IQ score (suggesting a difference in projection, but not necessarily in intelligence).

This may equally explain the anomaly of the low-IQ-score Africans not showing intellectual disability.

But as I had stated earlier, in the first article, persons of different groups at equal percentiles of IQ within their respective groups may possess similar "intelligence" represented by capacity, c for academic achievement (as an alternative -- although a weak one today -- to g which is strongly tied to absolute IQ scores).

Egypt once used to run circles around the world. The Egyptian civilization was advanced and clearly beyond others. The other groups were there, and what had happened to their intelligence? Today, Egypt has an average IQ score of 81! Of course, the Europeans (and Americans of European descent) are the kings of today. But history tells us that some other civilizations had shown a form of world supremacy -- military or economic -- in the past. Babylon, Assyria, Medo-Persia.

It may appear as if we are beginning to descend into pseudoscience. But everything adds up. 

We cannot deny the fact that becoming and sustaining a world power correlates with some form of intelligence. So what is the point? Perhaps, intelligence is a complex trait that manifests itself in alternate ways beyond just absolute IQ scores (remember Flynn effect?). Or between-group differences in IQ scores are differences in trait architecture projections.

This takes us to the topic of projection transformation or what I would like to call projection normalization. To equate the intelligence of persons of different groups at equal percentiles of IQ within their respective groups, we would have to transform their architecture projections or normalize them. Within this, lies the constant k. k is dependent on the intelligence trait architecture for a group.