Tag Archives: intelligence

Teachers and Intelligence

An individual’s performance is influenced, among other things, by his creativity, his motivation, his personality, and his intelligence. Intelligence can either be crystallized or fluid. Crystallized intelligence is in long term memory: it is what his knowledge, his expertise, his experience. Fluid intelligence is the central executive of working memory which controls what you think, what you pay attention to, and how you reason. Besides the episodic buffer that provides context, fluid intelligence is composed of a visuo-spatial sketchpad associated with scientific and mathematical reasoning, and also a phonological loop associated with rhetorical and verbal reasoning.

This is the context for some charts provided by the Educational Testing Service [PDF download], and already discussed by Education Realist, Razib Khan, and Steve Sailer.

Here is the chart for the verbal SAT score of teachers, which is a rough measure of their verbal and rhetorical:

Here is a chart for the mathematical SAT score of teachers, which is a rough measure of their scientific and mathematical reasoning ability:

Steve Sailer had the following thoughts:

Overall, public school teachers are pretty average for college graduates. It looks like they average about a quarter of a standard deviation lower on college admission tests than do average college graduates. But then college graduates are above average. With the exception of high school math teachers, teachers tend to score higher on the Verbal / Critical Reading section than on the Math section. That’s their job: to use words to explain stuff. But it also explains why they have trouble dealing with the flood of data that’s been incoming in recent years: thinking about statistics isn’t their strong suit.

My guess is that smarter teachers would probably be a good thing, so we ought to be thinking about ways to make the job of teaching more attractive to smart people. In general, smart people don’t like dealing with knuckleheads, so forcing teachers to carry most of the burden of discipline, a growing trend in recent decades, is a good way to keep smart people out of the business. You can instead use some of those gym teachers to run after school detentions instead of delegating most of the disciplining down to the teachers as happens in so many public schools desperate to avoid disparate impact lawsuits by not generating a paper trail of discipline actions carried out by the administration.

My take is if you want more lawyers and MBAs produced by our educational system, you should be happy with the status quo. If you think Science, Technology, Engineering, and Mathematics (STEM) are better at producing wealth, though, you should be unhappy for this.

On the other hand, if we don’t start treating teachers as professionals we’re going to end up with idiot-proof instructional technology anyway, so it might not even matter.

The Hierachy of Intelligence(s)( Tests)

In the context of an attack on Howard Gardner’s theory of multiple intelligences (10 page PDF), David F. Lohman (of the University of Iowa) presents this visualization of the hierarchies of intelligence tests:

Hierarchy of IQ Tests

The closer to the center, the more general lintelligence (“g”) loads on the test. Some tests, such as identifying the correct endings of words, reading speed, or listening comprehension test “g” more indirectly than measures of verbal achievement, paper folding, or necessary arithemetic operations.

A good example is the Test Necessary Arithmetic Operations. This test was devised by Guilford to measure a specific cell in his Structure of the Intellect Model. Each item presents a short word problem. The examinee’s task is not to solve the problem, but to say which two operations she would use, and in what order. There are four operations: add, subtract, multiply, and divide. Thus, problems do not require advanced mathematics. Yet in the sample of over 100 Stanford undergraduates who were administered most of the tests in Figure 2, Necessary Arithmetic Operations had one of the highest loadings on the [fluid intelligence] factor (Marshalek, Lohman, & Snow, 1983).

I meant this because of Mark’s discussion of Dr. James Flynn on the Flynn Effect. Essentially, the Flynn effect explains the large-scale increase in measured general intelligence over the 20th century as reflecting increased society-wide patterns of practice on subtests. This implies two things: first, that tests should be renormalized every so often to make sure they still measure “g,” and not practice. Second, that ability improves with practice.

It strikes me that, when properly normalized, IQ measures something psychobioneurological… perhaps not working memory exactly, but something not too far apart from that concept.

This has implications for the heritability of IQ. Most obviously, the more environment changes, the more change in performance can be traced to the environment. (Of course, as environments become more similar, more of the variation in the population will be explained by environments.)

General intelligence, working memory, and how American Public Schools hurt those who need them most

Colom, R., Rebollo, I., Palacios, A., Juan-Espinosa, M., & Kyllonen, P.C. (2004). Working memory is (almost) perfectly predicted by g. Intelligence, 32(3), 277-296. doi:10.1016/j.intell.2003.12.002.

Andrew Sullivan, Ezra Klein, Half Sigma, and other bloggers of note are going around on the question of the heritability of intelligence in general, and the possibility of biological causes for the differences in general intelligence obsered in different groups. While occasionally people speak carelessly, it’s remarkable how far the Standard Social Sciences Model (SSSM) of all human differences being the result of different environments has already collapsed. There are three traditional ways to attack the notion in biologically-driven racial differences in general intelligence

  1. There is no such thing as general intelligence
  2. There are no such things are races
  3. The environmental conditions in which the races tend to exist are unequal

The first two criticism are discredited. One can deny g or ancestry in the same way that one can deny darwinian selection or the old Earth: through determined dogmatism.

The third criticism remains, if only because of the horrifying inequalities in the world today. Of course, environmental inequalities can rapidly turn into biological inequalities. One only needs to look at the Inbred Gap to know that. Yet it’s also true that one can be trained to perform better on any subset of tests that are used to measure general intelligence. Thus the Flynn Effect: this or that measure will suddenly deviate from the rest, causing illusionary growth or shrinkage in differences.

One measure that very closely approximates g (“(almost) perfectly predicts,” in the word of the paper’s excited authors) is working memory.

This article analyzes if working memory (WM) is especially important to understand g. WM comprises the functions of focusing attention, conscious rehearsal, and transformation and mental manipulation of information, while g reflects the component variance that is common to all tests of ability. The centrality of WM in individual differences in information processing leads to some cognitive theorists to equate it with g. There are several studies relating WM with psychometric abilities like reasoning, fluid intelligence, spatial visualization, spatial relations, or perceptual speed, but there are very few studies relating WM with g, defined by several diverse tests. In three studies, we assessed crystallised intelligence (Gc), spatial ability (Gv), fluid intelligence (Gf), and psychometric speed (Gs) using various tests from the psychometric literature. Moreover, we assessed WM and processing speed (PS). WM tasks involve storage requirements, plus concurrent processing. PS tasks measure the speed by which the participants take a quick decision about the identity of some stimuli; 594 participants were tested. Confirmatory factor analyses yielded consistently high estimates of the loading of g over WM (.96 on average). WM is the latent factor best predicted by g. It is proposed that this is so because the later has much in common with the main characteristic of the former.

Working memory allows you to make sense of information, so that you can remember it. It is most important in that it makes it easier to memorize things. This also explains why school appears to lower general intelligence of high-performing populations, such as Chinese: if you are in an environment where high academic achievement is socially punished, excess working memory capacity naturally atrophies. Similarly, this may explain why the heritability of g increases in life: once out of the socialized public schools, an individuals’ environment is more under his control, and an individual that enjoys tasks that involve the comprehension of complex materials will strengthen those neural connections more.

If g really is working memory, the educational implications are huge. The soft bigotry of low expectations is especially brutal to those apparently with low working memory capacity. Because working memory does not matter once a task is memorized. Memorization is the way-out of the trap of low working memory. And what’s needed for memorization is clear: practice, academic discipline, and practice. Yet who believes that fifty years after Brown v. Board of Education most majority-black schools are models of academic seriousness and discipline?

Even more tragic — if the link between general intelligence and working memory is strong — working memory is trivially easy to test. There’s no need for race-conscious policies at all to battle what may be the worst racial inequality through education. We could close much of the achievement gap, regardless of average biological differences between races.

Instead, we have America’s public schools.

Never believe it. We’ve fought too hard.

Courtsy of Half Sigma, an exceptionally good article from Slate.com on liberal creationism. The article is solid and unremarkable, other than for its intended audience. What’s most interesting are the comments it generated from Salonists. I lurked in the forum, and found some zingers.

My favorite is so over-the-top I wonder if i is a satire:

I don’t care what the “scientific evidence” says – I’ll never believe the “truth” that the races aren’t equal. We’ve fought too hard for too long. I also am very disappointed to see Slate publish this pablum – maybe in the National Review or whatever rag Herr Bush reads, but not Slate.

Another clearly disaproves of gnxp:

Jason Malloy is a member of one of the most notorious racist blogs on the Internet — Gene Expression. The bloggers there claim blacks and Hispanics are geneticially inferior — a missing link between apes and humans. Ironically, Malloy himself is at least a quarter black, but can pass for white. Hatred of his own ancestry seems to motivate him. He has no background whatsoever in science.

Steveangr takes a pot-shot at christian Creationism while defending his own kind:

Christians go through a phase because they were indoctrinated to sth that is false and now they have either to come in terms with the false bearing or choose the right thing which is different from their upbringing. Believing that there is no inherent genetic trait to intelligence, is not only supported by science -thus far- but it is wrong to thing otherwise, it’s yours the pit you have dug there…

The comments I linked to were about average. Some were well meaning but misinformed. Others were emotional and clearly hurt. A few trotted out things they clearly learned in a 100-level class, and authoratively stated that anyone who took a freshman-level class would realize.

All in all, a good read if you’re looking for dogmatism.

The Consequences of Brain Drains in Developing Countries

“They say there is a brain drain. Let these decayed brains flee. Do not mourn them, let them pursue their own definitions of being. … Don’t be concerned. They should escape. [Iran] is not a place for them to live any more. These fleeing brains are of no use to us. Let them flee. If you know that this is no place for you, you should flee too.
– Ayatollah Ruhollah Khomeini [English, Farsi]

Recently, Steve wrote that he was surprised I had not addressed brain drains (the flight of the educated elite from less productive to more productive countries) before. So in this small post, I will. Specifically, I will address the Brain Drain among developing countries, using as examples Ethiopia, China, and Iran.

Intelligence is heritable. When living standards are relatively close, about 50% of variation in intelligence is explained by genetics, about 10% by home environment, and about 40% by “individual differences” (in statistical jargon, the error term). In the United States, where standard of living that much of home environment is itself driven by genetics, intelligence seems to be 70% heritable. In poor countries with large class differences, however, home environment counts for a lot. This matters because the more of intelligence that is explained by genetics in a country, the worse the long term consequences of the brain-drain will be.

Thus, the brain drain has minimal long-term consequences for Ethiopia. Ethiopia is a largely agricultural, tribal-based society where individual differences in intelligence doesn’t determine much. You are much more likely to be well fed and have children with wives/mistresses if you are well connected than if you are smart. The intellegentia of Ethiopia is largely determined by political connections, not DNA.

Likewise, the brain drain has minimal long-term consequences for China. Among other reasons, China is a huge country that has a greater population than Europe and the Western Hemisphere combined. A statistically important fraction of China’s population is simply unable to leave, as the loss of even .02% of China’s population would be enough to double the population of Canada. And even apart from this, China has about 900,000,000 peasants who struggle to survive, let alone achieve the higher education that marks one as intelligent.

However, the brain drain has drastic long-term consequences for Iran. Iran’s descent system of public education allows most Iranians a fair shake at greatness. Iran’s objective college entrance tests root out corruption and nepotism in the admissions process. In all likelihood, 50% of the variation in intelligence is heritable in Iran, just as it is in other modern countries.

Every year more than 150,000 educated young people leave Iran for countries such as the U.S. and Canada. Some 4 million Iranians now live abroad.” At this rate, within a decade 10% of Iran’s population will no longer live in Iran. Unless a massive flight back to Iran takes place, these expatriates and their families will become assimilated into western society and join the rest of the melting pot, losing a desire to return to the old country.

It would be an exaggeration to say that the top 10% of Iranians will have left… But perhaps not much of one to say that a third of the top 30% will have fled. While the drop in Iranian fertility will allow more of society’s resources to be focused on fewer children, the genetic loss the brain drain causes will be around for generations. Low intelligence is behind much of Africa’s problems of state-failure and institutionalized misery. The longer the brain drain continues in Iran, the dimmer Iran’s future will be.

In conclusion: The Brain Drain presents long-term troubles as it reduces the genetically factors that lead to high intelligence. This is only a problem in states where living standards are comparable and good systems exist to educate the general population. Iran’s successes in providing a decent life and good educational possibilities for its citizens make her future worse than those of her more corrupt fellow states.

Global Guerrillaism or Idiocy?

There’s an ongoing debate about low intelligence, environmental instability, and the livint standards of a country. It’s worth reading about, but I will set that aside to re-join the discussion on global guerrillas, with my friends Schloky, Soob, and others.

I’ve criticized global guerrilla theory before. It is unfalsifiable, lacks metrics, and lacks any explanation of why someone would become a global guerrilla. About the only thing going for the theory is that there are “failed states” and “hollow states” in the world. Global guerrillas would want to create hollow states, so the argument goes, therefore, these hollow states may have been caused by global guerrillas.

Of course, this is like arguing in favor of aliens by saying there are lights in the sky. And it can be combated in the same way. The “alien hypothesis” for UFOs is not taken seriously because far more boring explanations (misidentified planets, military craft, etc.) work equally well. Likewise, the “global guerrilla” explanation for failed states falls because something far more obvious prevents societies from being stable.

Take, for example, Africa… a continent riddled with failed states since decolonization.

The African Gap

According to the latest failed states index, the hollowest countries in Africa are Sudan, Somalia, Zimbabwe, Chad, Ivoery Coast, Congo, Guinea, Central African Republic, Uganda, and Nigeria. An evidence of a global guerrilla swam? Hardly: the mean intelligent quotients of these countries are 72, unreported, 66, unreported, unreported, 65,59, unreported, 73, and 67.

Why don’t African states get better? Because the population, on the whole, has the intelligence of 12-year-olds.

Intelligence, besides making one “smarter,” is correlated with the ability to delay gratification and the ability to solve problems — precisely those skills needed for civilized life

To be persuasive, global guerrilla theory needs to explain failed states in a way better than other explanations. Lack of intelligence, combined with economic structure, alone is enough to explain most failed states. So why bother with “global guerrillas”?

Update: Tom adds his thoughts.

Improving Americans

Barnett, T.P.M. 2007. I like it! Numbre three on the list! Thomas P.M. Barnett :: Weblog. May 24, 2007. Available online: http://www.thomaspmbarnett.com/weblog/2007/05/i_like_it_number_three_on_the.html.

I like this idea a lot (whenever Tom Barnett and Tom Friedman are on the same page, good things happen):

Money quote:

I think any foreign student who gets a Ph.D. in our country — in any subject — should be offered citizenship.

Definitely add this one to the list, after civilians who work for the SysAdmin and those who join our armed forces.

I like it!

Besides the short term effects, the biggest effect of granting citizenship to Ph.D.s is long term: the improvement of the American Race.

Flag of the United States of America

Intelligence is highly heritable — something like 50% of variation in general intelligence is explained by genetics. While clearly countries in the Gap do not have social systems to give their citizens an equal chance, it’s also clearly that those who do make it to the United States and succeed in a doctoral program are both hard working and smart.

So having an immigration regime which focuses on attracting intellligent individuals has the lasting effect of increasing the intelligence of Americans generally. It allows the United States to continue her policy — taking the best, brightest, and hardest-working — from the rest of the world.

I like it!

Askhanazim Jewry, g, and Higher Education

Askhanazim Jewry, g, and Higher Education

Jaschik, S. 2007. ‘The Power of Privilege.’ Inside Higher Ed. April 11, 2007. Available online: http://insidehighered.com/news/2007/04/11/soares.

A treasured friend & trusted reader sent this article in, which discusses possibly antisemitic reasons for the introduction of the SAT test in Yale University. The piece spends a lot of time on the quirks of the New Haven, Connecticut school, so I’ll just quote one part of it and talk in more general terms:

If colleges more closely understand their histories, Soares said, they might be more likely to adopt truly progressive policies today. His book ends with a series of recommendations along those lines, not just for Yale, but for other elite colleges. He calls for affirmative action policies based on socioeconomic status, a de-emphasis on standardized testing, and the elimination of preferences that defy true meritocracy (such as those for legacies and athletes).

Favoring athletes, he said, makes very little sense if talking about the social mission of higher education. Even at top universities, this has become “the doorway in,” and counter to the images many people have of athletics as a pro-diversity force on campuses, most of the beneficiaries are white. “What is it that athletics contributes to higher education? Why is it a part of higher education?” Perhaps showing the impact of his Oxford history, Soares noted that the admissions preferences offered by top American colleges make no sense to educators anywhere else in the world. “At Oxford and Cambridge, you are not going to be admitted just because you are good on the rugby field.”

Trying to discriminate against Jews by factoring in g (general intelligence would be odd, as Ashkenazim (“northern European”) Jews apparently have higher average g than most other races. This seems to be a result of intense selection pressure on Jews in the past thousand years, as cruel and mean regimes adopted policy after policy to limit Jewish mobility, wealth, and reproductive success. Average- and below-average Jews were selected against, while above-average Jews were selected for, by the European environment relative to other Europeans.

Thus, institutions of higher education used a variety of methods to keep Jews out, by defining merit as something other than general intelligence. From a century ago, Eastern universities used the idea of the “whole man” to discriminate against Jews. Because Jewish cultural traditional is relatively unathletic, Jewish history in Europe kept them seperated from the land and much physical exertion, and relatively higher rates of historical inbreeding (owing to ghetto living conditions), Jews were at a disadvantage under the “whole man” criteria. Likewise, modern affirmative action is a method of limiting the success of Jews and other market-oriented minorities.

See also: My series on feminism, leftism, and cash, covering the SAT and computer science.

Leftism, Feminism, and Cash

Agnostic. 2007. New GRE cancelled – the cost of attempted gap-reduction? Gene Expression. April 4, 2007. Available online: http://www.gnxp.com/blog/2007/04/new-gre-cancelled-cost-of-attempted-gap.php.

First, an excerpt from the excellent blog piece. Then a short discussion by me:

The NYT reports that a completely revised GRE has been deep sixed, not merely delayed (read the ETS press release here). The official story is that there is some insurmountable problem with providing access to all test-takers, an issue apparently too complicated for ETS to bother trying to explain it to us. You figure, since this was such a huge project that was suddenly halted, they’d want to clearly spell out why they dumped it — unless that’s the point. Although I’m no mind-reader, the true reason is pretty obvious: the made-over test was designed to narrow the male-female gap at the elite score level, but this diluted its g-loadedness such that it couldn’t reliably distinguish between someone with, say, a 125 IQ and a 145+ IQ, which is what graduate departments who rely on super-smart students worry about. Rather than admit that this psychometric magic trick went awry and lopped off a few limbs of g-loadedness, they spun a yarn about access to the te


We now ask why ETS intentionally stripped the SAT of some of its g-loadedness? Certainly not because they discovered IQ had little value in predicting academic performance, or that some items tap g more directly than others — so why re-invent the wheel? Since scores on various verbal tasks highly correlate, this change cannot have affected much the mean of any group of test-takers. But if getting a perfect score required scoring correctly on, say, 10 easy questions, 5 medium, and 5 difficult (across 3 sections), a greater number of above-average students can come within striking distance of a perfect score if the new requirement were 10 easy, 9 medium, and 1 hard. I don’t know exactly how they screwed around with the numbers, but that’s what they pay their psychometricians big bucks to do. Now, reducing the difficulty of attaining elite scores, without also raising mean scores (as with the 1994 recentering), can only have had the goal of reducing a gap that exists at the level of variance, not a gap between means. This, then, cannot be a racial gap but the male-female gap, since here the difference in means is probably 0-2 IQ points, although male variance is consistently greater.

In other words..

  • Some time ago, the SAT released a new test that kept the pre-existing group means (so that jews still scored higher than scotch-irish, and that asians still scored higher than blacks) but made it easy for pretty-good students to score the same as very-good students
  • The GRE seriously considered, openly planned on, announced, and then suddenly rejected a similar plan.

Ultimately, this is a tale of political correctness and money. Especially since fired Harvard President Larry Summers publicly asked if there was a genetic component to sexual differences, but since the birth of feminism in the early 20th century, the “polite” opinion is that males and females are genetically identical and apart from a few organs the sexes are in no way different. Thus intelligence testing, which consistently reveal that the highest-scoring males have higher intelligence than the highest-scoring females, is embarrassing. While the SAT and the GRE are technically aptitude tests, they are also rough measures of intelligence so the same issues that impact IQ testing impact the SAT and GRE.

The easy way to remove this shame is to ignore it, so the SAT lowered the bar for the highest-scoring students. Thus the highest-scoring females would score exactly the same as the highest scoring males – with a perfect 2400R.

For undergraduate schools this is just fine. Anything that increases the student body size while avoiding public embarrassment puts money into the hands of the Universities,. Likewise, compared to graduate schools undergrad institutions tend to be non-competitive (excluding quotized areas sex as race, where it is hard to change race from penalized categories such as oriental or white to preferred categories such as black or indian). Thus, the SAT combined easy leftism with easy commercialism: the change stands!

For graduate schools this is not fine. Graduate students are investments in ways that undergrads just aren’t. Grad students take up more of professors’ face time, often have the responsibility of assisting in research or teaching undergraduates, and are actually paid. Thus a non-productive grad student can more easily become a cash dog than can a non-productive undergrad. There, within grad schools capitalism defeated easy leftism: the change is rejected!

Update: Darth Quixote at gnxp examines the results of the latest SAT.