Tag Archives: Arthur Jensen

High range power tests part 2

04 Thursday Mar 2021

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As we saw in in part 1, a reader had some questions about high range power tests.

The reader asks:

What, if any, capacities might tests of the high-range “power” format disclose that standard IQ tests cannot, or, at least, do not?

As I mentioned in part 1, they probably measure the personality trait TIE (Typical Intellectual Engagement) and perhaps some cognitive abilities that conventional IQ tests miss like executive function. And as discussed in the comment section, they’re probably less sensitive to test anxiety because you can take them in a relaxed non-threatening environment.

But there’s more.

Creativity

Chris Langan stated:

Certain high-ceiling intelligence tests, generically called “power tests”, are composed of extremely
difficult items requiring higher levels of problem-solving ability than the items on ordinary IQ tests. Since these items
usually have no known algorithms, their solutions cannot be looked up in a textbook, and where subjects do not know each
other, one must rely on intrinsic problem solving ability.

From Discussions on Genius and Intelligence Mega Foundation Interview with Arthur Jensen pg 23

Arthur Jensen replied:

…Solving problems, or even thinking up problems, for which there are presently no algorithms, takes us into the
realm of the nature of creativity. There are as yet no psychometric tests for creativity in a nontrivial sense. We can’t
(yet) predict creativity or measure it as an individual trait, but can only examine its products after the fact.

From Discussions on Genius and Intelligence Mega Foundation Interview with Arthur Jensen pg 24

I find Jensen’s reply curious. He just admitted that the type of psychometric test Langan was describing involved creativity and then denied any tests measure it. Although I was extremely impressed by the questions Langan asked, he should have asked for clarification here.

The so-called distinction between creativity and intelligence is interesting. Intelligence is commonly defined as your ability to problem solve, but what is creativity if not original solutions to problems? So I guess people deny conventional IQ tests measure creativity because the solutions aren’t original enough. Why don’t conventional IQ tests require original solutions? Because such solutions would be so numerous that the test scoring manual could not include them all, or if there’s only one, in order for it to be original, too few people would discover it, making it useless for mass testing.

But because untimed power tests include many problems very few people can solve, by definition they measure original problem solving and thus creativity. One could claim that the problems must have social significance to be true measures of creativity, but what is significant is context dependent and creativity, like all traits, is relatively stable.

For example, before coronavirus became a global pandemic, creating a vaccine would have been unimportant but if someone had created one in 2018, they wouldn’t think “if I had only waited until 2020, I could have been creative, instead I’m merely extremely intelligent”. There could be a parallel universe where problems on the Mega Test have enormous real-world implications, while discovering relativity is merely a hard item on the Mega Test. Creative is something you either are or aren’t, it’s not something that changes with the social value a particular society puts on a given problem at a given time.

Autism?

Commenter “Mug of Pee” jealously goes ballistic when anyone values tests other than the ones he scored high on (SAT, GRE). In order to devalue such tests, he’s claimed, somewhat facetously, that the Mega Test measures autism. While it’s true that the Mega Test requires you to focus for very long periods of time (an autistic trait), it also requires you to be interested in a wide variety of subjects, as opposed to the narrow autistic focus. I suppose there could be some autistics whose area of obsession is just puzzle solving in general, but I know of no confirmed cases.

Without doing brain scans, autism is much harder to measure as objectively as IQ but if forced to do so, I would use one’s composite score on the following four variables:

  • income adjusted for IQ (the lower the more autistic)
  • occupational status adjusted for IQ (the lower the more autistic)
  • head size adjusted for IQ (the larger the more autistic)
  • theism adjusted for IQ (the higher, the less autistic)

In other words, autistics would tend to be those who are poorer, less respected, bigger brained and less theistic than their conventional IQs predict. Anecdotal evidence suggests people with high Mega Test scores would fit the first three criteria, but perhaps not the fourth. However I’m assuming a linear relationship between IQ and all these variables. If at the highest levels, IQ predicts “success” in a curvilinear way, we might find that the socio-economic underachievement of some Mega society members is not atypical of their IQs as measured by conventional tests (with high ceilings).

More research is needed.

speed vs power tests & the nature of g

14 Thursday May 2020

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A reader wrote:


My first question: although IQ tests purports to be designed empirically, it feels like the weighting of speed vs. accuracy is completely arbitrary, whats up with that?

The way I see it, IQ tests are just a sample of all your cognitive abilities. But because no one knows the nature and number of every cognitive ability in the human mind, all psychologists can do is select an arbitrary sample that is as large and diverse as possible. Luckily, all cognitive abilities appear to be positively correlated and by prioritizing cognitive abilities that correlate well with every other known cognitive ability, the total score presumably predicts unidentified cognitive abilities also.

The reader continues:

I don’t think any IQ tests score you on speed, but most of them have a time limit that’s not long enough for the average person to complete it, giving people who can finish it faster an advantage.  While there’s certainly a correlation between one’s speed of reasoning and quality of reasoning, they seem to me like ultimately seperate qualities, yet IQ tests tend to lump them into one. For example, who is smarter, a person who finishes a test in time with 60% accuracy and is confident he got everything right, or a person who finishes half the test before the time runs out so gets a 50% but could have gotten 100% if given twice the time.

Some IQ tests do provide subscores for the so-called speed factor (the Processing Speed index on the WAIS-IV for example) but most timed IQ measures use speed as a convenient way of increasing the test’s difficulty, not because they’re trying to measure speed per se.

For example on a Wechsler spatial subtest, 15% of 16-year-olds are capable of solving every item within the time limit (which is a few minutes for the hardest items), but by giving bonus points to people who can solve the easy items within 10 seconds and the hard items within 30 seconds, only 0.1% can get a perfect score. So the use of time bonuses increases the test’s ceiling by two whole standard deviations without going to the trouble of creating more difficult items that would make the test too long.

When time bonuses are not given, a lot more people score perfect but the rank order of people remains virtually identical especially at age 85 to 90.9 where the correlation is 0.99! (WAIS-IV Technical and Interpretive Manual, Appendix A). The correlation is slight lower at younger ages (but still 0.93+) because of all the ceiling bumping when no time bonus is given. Such absurdly high correlations prove that when used judiciously, time bonuses merely add ceiling without changing the nature of what is being tested.

On group administered tests, the time limits not only don’t typically affect the rank order of scores much, but they don’t even increase the ceiling much. Arthur Jensen has reported that that when the Otis verbal’s time limit was increased by 50% (45 minutes instead of 30) , the average score only increased by 1.5%. When the Otis non-verbal time limit was increased by 150% (30 minutes instead of 20), the average score increased by only 1.7%, and when the Henmon Nelson increased its time limit by 67% (50 minutes instead of 30) scores increased by 6.3% (Bias in Mental Testing, 1981).

The notion of quick superficial thinkers vs slow profound thinkers is probably fallacious. People who do well on the Wechsler Processing Speed index actually have slower brains than people who do well on the untimed Raven Advanced Progressive Matrices. Once you control for general cognitive ability (the g factor), psychometric speed and has no correlation with reaction time (The g Factor by Arthur Jensen).

The reader continues:


My second question, kind of related to the first: what actually is the g-factor? The idea is that g is a construct that links the performance of all cognitive tasks, but how can you actually calculate such a number? It makes sense to me to, say, measure the g-loading of a sub-test with respect to a full IQ test, but how can you measure the g-loading of an entire IQ test? Is it just the test’s correlation to all IQ tests? Wouldn’t that just measure how close the test is to the average IQ test? Also, the idea of a g-factor would seem to require a definition of what’s “general”, and that doesn’t seem like something that can be done empirically. Like if we lived in a society entirely base in music, then would the g-loading of piano skill tests be higher than math tests? And do tests of speed or tests of quality have higher g-loading? Then again, I haven’t read up on much of the literature so I could have some major misunderstandings.

In theory g is the source of variation that all cognitive abilities have in common so the larger and more diverse the battery of subtests from which g is factor analytically extracted, the more likely g reflects something real (as opposed to an artifact of test construction). If we lived in a society based on music, everyone might reach their biological potential for piano playing, while math might be esoteric trivia, so the former may indeed become more g loaded than the latter in that context. However the g loadings of novel tasks, that are not practiced in either our society or the musical one, should have similar g loadings in both.

Arthur Jensen told racists to BUZZ OFF!

11 Saturday Apr 2020

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In 1969, Arthur Jensen wrote an article in the prestigious Harvard Educational Review [HER} that transformed him from highly respected, but little known scholar, to one of the most controversial and influential psychologists of all time. So influential was Jensen, that a new word entered the English language: Jensenism; and a platoon of famous scholars made a career out of trying to debunk him.

The three tenets of Jensenism are:

  • Compensatory education fails to improve the IQ or scholastic skills of culturally deprived kids.
  • Genetics explains more of the variance in American IQ than culture.
  • Genetics likely explains some part of the 15 point black-white IQ gap in the United States

So powerful was Jensenism that President Nixon assigned his staff to report to him on Jensen’s HER article. In 1974 Daniel Patrick Moynihan stated, “The winds of Jensenism are blowing through Washington with gale force.”.

Frank Miele writes:

According to John Ehrlichman, Richard Nixon told him that he believed America’s Blacks could only marginally benefit from federal programs because they were genetically inferior to Whites. All the federal money and programs we could devise could not change that fact. Though he believed that Blacks could never achieve parity in intelligence, economic success, or social qualities, we should still do what we could for them, within limits, because it was the “right” thing to do.

From page 151 of Intelligence, Race and Genetics by Frank Miele

While Nixon was clearly a Jensenista, Jensen was a self-described liberal, stating:

In fact, I voted for Johnson in the 1964 presidential election. I felt strongly enough about it that I voted by absentee ballot because I was in London on sabbatical leave working as a Guggenheim Fellow in Eysenck’s department.

I believed in the Great Society proposals, particularly with respect to education and Head Start. When I returned to California I gave talks at schools, PTA meetings, and conferences and conventions explaining why these things were important and should be promoted. I have always been opposed to racial segregation and discrimination. They go against everything in my personal philosophy, which includes maximizing individual liberties and regarding every individual in terms of his or her own characteristics rather than the person’s racial or ethnic background. How could I think otherwise when at the time I had been steeped in Gandhian philosophy for over 20 years?

From pages 33-34 of Intelligence, Race and Genetics by Frank Miele

But by 1969 he was clearly less liberal when it came to compensatory education for disadvantaged kids. Was he changing his views to gain political traction in Nixon’s more conservative America? Jensen states:

Absolutely false! That way of thinking is completely foreign to me. I am almost embarrassed by my lack of interest in politics and I was even less interested in those days than I am now. The idea of providing any kind of “ammunition,” scientific or otherwise, to help any political regime promote its political agenda is anathema in my philosophy. One always hopes, of course, that politicians will pay attention to scientific findings and take them into consideration in formulating public policy. But I absolutely condemn the idea of doing science for political reasons.

I have only contempt for people who let their politics or religion influence their science. And I rather dread the approval of people who agree with me only for political reasons.

From page 35 of Intelligence, Race and Genetics by Frank Miele

Nonetheless, some racists reached out to Jensen, for help. Jensen states:

After the publicity surrounding the HER article, I did receive a number of letters from so-called citizens’ groups in various Southern states, asking if I would write letters to their local newspapers in support of racial segregation in public schools. I replied that I was, and always have been, absolutely opposed to racial segregation of any kind. One of these people wrote back calling me “just another Berkeley pinko!” He at least gave me the satisfaction of knowing I had angered him.

From page 21 of Intelligence, Race and Genetics by Frank Miele

So after 30 years of arguing that races differ in genetic IQ, what did Jensen think of affirmative action. Jensen states:

When the original concept of Affirmative Action was just catching on in the 1960s it was not a quota system. That only came later. I approved two main facets of its original intent, and I still do: (1) We should make special efforts to ensure that historically underrepresented minorities are fully aware the educational opportunities in colleges and universities, in job training programs, and in employment opportunities are open to all, provided they meet the usual qualifications; and (2) colleges and universities, job training programs, and employers should actively seek out and recruit minority persons who could qualify by the usual standards, including the use of academic talent searches at the high school level, special inducements, and scholarships to encourage academically promising minority students to go on to college.

From page 177 of Intelligence, Race and Genetics by Frank Miele

Arthur Jensen lived from 1923 to 2012.

Why does shared environment affect some IQ tests more than others?

04 Saturday Apr 2020

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Using twin studies, scientists divide phenotypic variation into three categories: DNA variation, shared environmental variation, and unshared environmental variation. Shared environment are all the experiences MZ twins reared together have in common (same upbringing, same schools, same womb) while unshared environment are all the experiences they don’t share (position within the womb, getting hit on the head, having an inspiring teacher).

The best estimate using massive datasets suggest that within Western democracies, DNA explains 41% of IQ variation at age 9, 55% at age 12, 66% at age 17, and 74% in adulthood. By contrast shared environment explains 33% at age 9, 18% at age 12, 16% at age 17, and 10% in adulthood (Bouchard 2013, figure 2). That leaves unshared environment explaining 26% of the variation at age 9, 27% at age 12, 19% at 17, and 16% in adulthood.

You don’t have to believe these associations are causal, but they are real. They’ve been more or less replicated using studies comparing (1) MZ twins with DZ twins, (2) MZ twins raised apart, (3) unrelated people reared in the same home. Although all of these methods depend of different assumptions, they all converge on the same conclusion: the predictive power of DNA skyrockets from childhood to adulthood while the predictive power of shared environment plummets. The same pattern (known as the Wilson effect) has also been observed for other phenotypes and in other species.

But why? Shouldn’t environment get more important as we age since experience has increasing time to accumulate? One theory is that more and more genes become active as we age. A more popular theory is that we select environments that maximize our genotype, so environment becomes just a magnifier of genes, not a causal force in its own right. So genetically smart people will stay in school and genetically strong people will lift weights and take steroids etc. People invest in where they’re more likely to be rewarded.

But here’s where things get really interesting. The Wilson effect behaves differently on different types of IQ tests. In his book Does your Family make you smarter? James Flynn notes that cognitive inequality increases from childhood to later adulthood (because good genes cause good environments and bad genes cause bad environments, the smart get smarter and the dumb get dumber, relative to the average person their age) but this pattern is much more pronounced on some tests than others.

Flynn describes three types of tests:

  • Type 1: Tests that show large family effects (shared environment) that decay slowly. This include tests involving vocabulary (define “rudimentary”), general knowledge (How old is the Earth?) verbal abstraction (how are a brain and a computer the same?) and social comprehension (why do you need a passport to travel?)
  • Type 2: Tests that show small family effects that decay fast. These include spatial manipulation (use these two triangles to make a square) and noticing incongruities (what’s missing or absurd in a picture of a common object or scene).
  • Type 3: Tests that show that large family effects that decay fast. These tests include clerical speed and arithmetic.

Flynn argues that type 1 tests involve skills that children learn from observing their parents talk, hence the large family effect. By contrast he says of type 2 tests:

Aside from the occasional jigsaw puzzle, they have no part in everyday life. Children never see their parents performing these cognitive tasks as part of normal behavior. Family effects are weak, even among preschoolers. Since these subtests match environment with genetic potential so young, they would be an ideal measure (for, say, 5-year-olds) of genes for intelligence.

From pages 53-54 of Does Your Family Make You Smarter? by James Flynn

In other words, Type 2 tests measure “novel problem solving”, while type 1 tests measure acquired abilities. A more provocative interpretation is type 2 tests measure real intelligence, while type 1 just measure knowledge and experience. This is the age-old distinction between aptitude tests vs achievement tests, culture fair vs culture loaded, fluid vs crystallized.

And yet Flynn largely rejects Cattell-Horn-Carroll’s theory that fluid ability (novel problem solving) is invested to acquire crystallized ability (accumulated knowledge) writing:

…fluid skill is just as heavily influenced by family environment as the most malleable crystallized skill (vocabulary) and therefore, neither skill deserves to be called an investment and the other a dividend.

From page 132 of Does Your Family Make You Smarter? by James Flynn

Flynn of course is referring to the greatest irony in the history of psychometrics and the biggest mistake of Arthur Jensen’s career: the Raven Progressive Matrices (long worshiped by Jensen and Jensenistas as the most culture fair measure of pure intelligence ever invented) is a type 1 test!

Which of the 8 choices completes the above pattern? Image from  from Carpenter, P., Just, M., & Shell, P. (1990, July)

But let’s not throw the baby out with the bath water. There’s no need to abandon CHC investment theory just because a major test got mischaracterized. But at the same time, it doesn’t feel right to reclassify the Raven as a crystallized test, Research is needed to understand why the Raven is so culturally sensitive when it superficially looks like a measure of novel problem solving. Is it measuring some kind of implicit crystallized knowledge we’re not conscious of like being familiar with patterns, columns and rows and reasoning through the process of elimination, or are the family effects on the non-cognitive part of the test (having the motivation to persist and concentrate on such an abstract task). Flynn argues that the brain is like a muscle, but if so, the Raven is an exercise most have never done before, so why isn’t it a type 2 test?

Flynn might argue that if your family helped you with abstract problems in algebra or had philosophical discussions about hypothetical concepts, you’ve been exercising for the Raven all your life, but this seems like a bit of a stretch. All the research shows that cognitive training has narrow transfer (i.e. practicing chess will only make you slightly better at checkers, and not at all better at scrabble) though perhaps the Raven’s uniquely abstract (general) nature allows it to slightly buck this trend.

If cold winters select for high IQ, do they do so directly or indirectly?

16 Monday Mar 2020

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In evolutionary biology, a spandrel is a phenotypic characteristic that is a byproduct of the evolution of some other characteristic, rather than a direct product of adaptive selection—–Wikipedia, March 15, 2020

Commenter Mug of Pee writes:

arctic peoples have large brains for a very NOT just so story reason; the exact same adaptation is found in arctic mammals and in ice age humans and it’s very simple, a big round head is more insulating than a small or long head, allen’s rule.

Arthur Jensen agrees writing:

climate also influenced the evolution of brain size apparently indirectly through its direct effect on head size, particularly the shape of the skull. Head size and shape are more related to climate than is the body as a whole. Because the human brain metabolizes 20 percent of the body’s total energy supply, it generates more heat in relation to its size than any other organ. The resting rate of energy output of the average European adult male’s brain is equal to about three-fourths that of a 100-watt light bulb. Because temperature changes in the brain of only four to five degrees Celsius are seriously adverse to the normal functioning of the brain, it must conserve heat (in a cold environment) or dissipate heat (in a hot environment). Simply in terms of solid geometry, a sphere contains a larger volume (or cubic capacity) for its total surface area than does any other shape. Conversely, a given volume can be contained in a sphere that has a smaller surface area than can be contained by a nonspherical shape, and less spherical shapes will lose more heat by radiation. Applying these geometric principles to head size and shape, one would predict that natural selection would favor a small head with a less spherical shape (brachycephalic) shape because of its better heat dissipation in hot climates, and would favor a more spherical (dollichocephalic) shape because of its better heat conservation in cold climates….

From The g Factor page 436

So even if cold climates didn’t require any extra intelligence to survive in, they did require more brain mass just to keep warm, and given the moderate causal correlation between IQ and brain size, they would have selected for intelligence indirectly as a byproduct of thermoregulation.

There is also likely a causal correlation between IQ and brain sphericity (independent of size) because a sphere is the shape that minimizes the distance between neurons and thus presumably maximizes brain efficiency.

So it seems that not only could cold winters have selected for high IQ directly because of the intelligence needed to survive the cold, but they also may have selected indirectly via thermoregulation of brain size and brain shape.

The question for HBDers is how do we test these three potential causes to determine how big a role (if any) each played in population differences in IQ?

IQ, social environment & DNA

17 Thursday Oct 2019

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Commenter RR argues that IQ tests measure social class. If by social class he means the home one grew up in, the following author begs to differ:

First, family has little effect on whatever cognitive abilities you have after the age of 17. While family environment is potent early on, its effects fade away to low level by age 17 and become insignificant by maturity. As you grow up, you move outside the family and go to school, become a member of a peer group (your close friends), find a job, and marry. You enter a current environment that swamps the lingering effects of family environment. Current environment is surprisingly self-contained: it influences one’s current cognitive abilities with very little interference from past environments. Most of us assume that your early family environment leaves some indelible mark on your intelligence throughout life. But the literature shows this simply isn’t so.

Second, once the influence of family disappears, the cognitive quality of your current environment tends to match your genetic quality. This is often called the tendency toward “gene-environment co-relation”. This means simply that if your genes are at the 90th percentile for cognitive ability, your current environment tends to be at the 90th percentile of the population for cognitive quality…In other words, chance events aide, genes and current environment tend to match, so whatever genetic differences exist predict cognitive performance without any need to take current environment into account.

You might think the above was written by Arthur Jensen, but it was written by Jensen’s most formidable opponent, James Flynn. It’s from pages 5 to 6 of Flynn’s book Does Your Family Make You Smarter?

Evidence in support of Flynn’s comments is a 2010 study by Haworth et al, where an astonishing 11000 pairs of twins from four different countries were intelligence tested. The results: heritability was 41% at age nine, 55% at age 12, and 66% by age 17.

66% is very similar to the WAIS IQ heritability found in the Minnesota study of twins reared apart, but Haworth et al compared the IQ correlation of MZ twins raised together with the correlation of DZ twins raised together (the classical twin study). If one assumes that both types of twins are equally similar in their environments (including prenatal), the greater IQ similarity found among MZ twins can only be explained by their greater genomic similarity. This is known as the equal environment assumption.

Critics claim that MZ twins raised together enjoy more similar environments than DZ twins raised together and so genes are getting undeserved credit for an environmental effect. However Arthur Jensen notes:

…some same-sex DZ twins look much more alike than others. In some cases their parents even wrongly believe that their DZ twins are identical twins, and they treat them as such by dressing them alike and giving them the same hairstyles and so on. But DZ twins whose parents and others had mistaken them for MZ twins are no more alike in IQ than other DZ twins or ordinary siblings who don’t look much alike.

Source: Intelligence, Race and Genetics by Frank Miele, pg 98

Indeed if people think MZ twins have more similar environments than DZ twins because they look identical, then it follows that same sex DZ twins should have more similar environments than opposite sex DZ twins because they too look more similar (and are treated more similarly) and yet the IQ correlation between same sex and opposite sex MZ twins are virtually identical.

Further support for the equal environment assumption comes from a study of 1,030 female-female twin pairs from the Virginia Twin Registry with known zygosity. About 15% of the twins disagreed with their actual zygosity, however perceived zygosity had no impact on the correlation between twins when it came to any of the five psychiatric disorders studied.