The Voldemort View: Weak, Semi-Strong, and Strong

My comrade in blogging Ed Realist uses the phrase “The Voldemort View” to describe the following proposition:

The Voldemort View: Mean differences in group IQs are the most likely explanation for the academic achievement gap in racial and SES groups.

Someone in comments asked if I subscribe to the Voldemort View, the View that Shall Not Be Named. The short answer is yes, as stated. The longer answer is something like this.

The Efficient Market Hypothesis (EMH) is an idea in economics that asset prices  (stocks, bonds, real estate) probably reflect all available information. The EMH comes in three flavors, weak, semi-strong, and strong.

  • Weak EMH: Prices reflect all market information. You can’t beat the market by looking at what happened to the price yesterday.
  • Semi-Strong EMH: Prices reflect all publicly available information. You can’t beat the market by reading up on the company.
  • Strong EMH: The market is efficient, reflecting all public and private information. The asset price is a full and complete measure of the “true” value of something, including expectations about the future.

The Weak EMH says you couldn’t, in 2006, beat the housing market merely by noticing what had happened to prices since 2000 where you were planning to buy; this is by and large true. Consider that Las Vegas, Phoenix, Brooklyn and San Francisco all increased in price greatly between 2000 in 2006, but while buying in Vegas or Phoenix in 2006 was a terrible idea, buying a single family home in Brooklyn or San Francisco in 2006, if you were willing to grit your teeth through a few bad years, would’ve been a great idea.



The Semi-Strong EMH says you couldn’t do some research, look at demographics of the people buying in each place in 2006 and tell that Brooklyn was a better bet than Phoenix (or that stocks were a better bet than real estate.) This is probably false, but not certainly false. Sure, a lot of people buying in Brooklyn had the kind of money where they could put down $800,000 cash, while a lot of people buying in Phoenix were getting Countrywide loans with zero down payment and zero documentation. On the other hand, some places that looked demographically similar (about half white, 1/3 black, and 1/6 other) and had a higher median income than Brooklyn have done a lot worse since 2006; for example, Chicago:


So, call the semi-strong EMH a draw.

The strong EMH says there was no housing bubble, there was just a “black swan” unpredictable event that eradicated what would’ve been endless growth in home prices in Phoenix, Vegas, and the Inland Empire east of LA. Sounds wrong to me.

So, I’ll propose the weak, semi-strong, and strong version of the Voldemort View (VV).

Weak VV: Mean differences in group IQs at the time of test taking explain the academic achievement gap in racial and SES groups.

Semi-Strong VV: Mean differences in group IQs that K-12 schooling cannot significantly affect explain the academic achievement gap in racial and SES groups.

Strong VV: Mean differences in group IQs are fully representative of “intelligence, broadly defined,” and of the value of schooling to different groups. 

The Weak VV is, as Ed Realist puts it, not a hypothesis but a fact. You can completely explain differences in 4th grade test scores by 4th grade IQ gaps, 8th grade test scores by 8th grade IQ gaps, and 12th grade test scores by 12th grade IQ gaps. In fact, the IQ gaps are larger than the test score gaps, in many cases; this is because the elementary school tests are often not that g-loaded (though that may be changing) and because schooling in minority-majority schools has been highly focused on academic subjects and test preparation.

The Semi-Strong VV is somewhere between a hypothesis and a consensus interpretation of the evidence. For example, James Heckman is widely hailed by liberals for providing evidence in favor of pre-K, but he doesn’t really believe that schooling (even pre-K) can greatly influence IQ and cognitive ability. Instead, he thinks early investments like pre-K and Nurse Family Partnership influence non-cognitive abilities, which show later benefits (completing school, not going to jail, sticking with jobs) independently of IQ. Here, for example, from one of his presentations on the Perry Pre-School Project, are the IQs of the Treatment and Control groups over time, showing-complete fade-out:


So the Weak VV is indisputable and the Semi-Strong VV is endorsed even by people you wouldn’t expect. What about the Strong VV?

The Strong VV is something of a metaphysical question. What is “intelligence, broadly defined” if it’s not IQ? Ed Realist quotes this passage from Stephen Pinker about the validity of IQ as a measure:

Pinker: I think you’re wrong about IQ tests in general. They’ve been shown to predict (statistically, of course) a vast array of outcomes that one would guess require intelligence, including success at school, choice of intellectually demanding professions, income (in a modern economy), tenure and publications in academia, and other indicators, together with lower crime rates, lower infant mortality, lower rates of divorce, and other measures of well-being. The idea that IQ tests don’t predict anything in the real world is one of the great myths of the intellectuals.

I’ve said before that I disagree with the Strong VV (“Against Unidimensionality”) because smart people are so very dumb so often and because while abstraction and inference are very valuable things, they aren’t everything.

For example, I spent the majority of my time as a teacher teaching 7th grade life science in a very diverse school, racially and socioeconomically (roughly 15% white, 25% black, 40% Hispanic, and 20% Asian.) The performance of kids in my class followed the distribution you would expect from differences in mean group IQ only very, very roughly. This makes sense, because 7th grade life science is a pretty concrete topic and I was doing my very best to make it more concrete. On the other hand, I taught an after-school course preparing kids for the New York Specialized High School admissions test (the test to get into Bronx Science and Stuyvesant), and while I had a lot of success preparing kids for that test by the standards of students citywide, it was exactly the kids you’d expect: upper-middle class white kids and the children of Chinese and South Asian immigrants. The test is a very g-loaded measure, it’s all logic puzzles and math problems much more difficult than those on the GRE. (In fact, I didn’t need to study for the GRE at all later on because the SHSAT, while given to 8th graders, is a much harder test.)

But does that mean that my 7th grade life science class didn’t involve any intelligence? It certainly seemed like the kids were using their minds, designing experiments and arguing about evolution and explaining how the circulatory system worked.

Arthur Jensen, one of the founding fathers of IQ research, described these differences in terms of “Level I and Level II” intelligence as follows:

  • Level I ability consists of rote learning and primary memory; it is the capacity to register and retrieve information with fidelity and is characterized essentially by a relative lack of transformation, conceptual coding, or other mental manipulation intervening between information input and output. Level II ability, in contrast, is characterized by mental manipulation of inputs, conceptualization, reasoning, and problem-solving; it is essentially the g factor common to most complex tests of mental ability and standard tests of intelligence.
  • Level I tasks were those that required little or no mental manipulation of the input to arrive at the correct output. A clear example of Level I ability is Forward Digit Span in which people recall a series of digits in the same order as that in which they are presented. Level II tasks, however, require some mental manipulation of the input in order to arrive at the appropriate response. A clear example of Level II ability is Backward Digit Span in which people recall a series of digits in the reverse order to that in which they are presented.

Jensen’s explanation is that IQ gaps between groups are mostly in “Level II” intelligence; lower average IQ groups can perform “Level I” tasks (rote retrieval, essentially) but not more complex manipulation.

This actually doesn’t match my observations all that well. It’s not about “rote versus complex,” it’s about “concrete versus abstract” and “socially-embedded versus individually-achieved.” The kids who could fix the classroom air conditioner or figure out why the fish were dying in the fish tank weren’t the kids who did best on written tests. The kids who learned the bones of the body when they were part of a dance with pulsating techno-background music everyone did together weren’t the kids who could go home and memorize them easily on their own. (In fact, the kids who could go home and study the bones on their own often hated doing the dance.)

This doesn’t mean the kids who fixed the air conditioner or liked doing the bones dance are going to go on and be huge successes in college and get high paying jobs. By and large, they aren’t, because college (the academic side, anyways) and the modern workplace are abstract, individualistic places. But it does, to me, say something about whether IQ represents “intelligence, broadly defined.”

One idea I’ve had is that, instead of Jensen’s distinction between Level 1 (rote) and Level 2 (complex) reasoning, a better distinction is one that became very well known recently in a different context: psychologist Daniel Kahneman’s separation of cognition into “System 1” and “System 2”:

• System 1 operates automatically and quickly, with little or no effort and no sense of voluntary control.
• System 2 allocates attention to the effortful mental activities that demand it, including complex computations. The operations of System 2 are often associated with the subjective experience of agency, choice, and concentration.
System 1: Fast, automatic, frequent, emotional, stereotypic, subconscious
System 2: Slow, effortful, infrequent, logical, calculating, conscious

Kahneman became famous and revered in large part because he identified a set of System 2 tasks that were extremely difficult for even very intelligent individuals to accomplish. Kahneman’s work is considered important and was the foundation of behavioral economics (showing why the Strong EMH is wrong, and providing the scientific justification for broader paternalism) because it appears to show departures from rationality by everybody– even super-smart people often make the mistakes he predicts. This finding has been used to elide over the fact that dual process cognition is every bit as much a theory of individual and group differences as it is a theory of universal departures from rationality. Many studies suggest that the ability to accomplish System 2 tasks in general, if you don’t just isolate those mistakes that everyone makes,  is in good part the same thing as IQ:

System 2 function should be related to measures of general intelligence, although System 1 function should be independent of such measures. Stanovich and West have demonstrated in a recent series of studies [6,26,36,37] that  mthe ability of participants to find normatively correct solutions to a range of inferential and decision making tasks was consistently associated with those who were high in cognitive ability as measured by SAT scores.

In some cases, indeed, as my experience teaching suggested, individuals can accomplish a task if it is concrete and relevant to prior information in a way that they can’t if it is purely abstract:

One of the most investigated reasoning problems in the literature is the Wason selection task (see Box 3). In an abstract, indicative version (Figure Ia in Box 3), it is known to be very difficult. However, in a realistic, deontic  version (Figure Ib), is it is quite easy. On the dual-process account, the former is difficult because it requires explicit and abstract logical reasoning of the kind that only System 2 can provide. With the latter task, however, the correct answer is strongly cued by relevant prior knowledge, reflecting System 1 processes [1].

wason selection task

This matches my experiences much more than Jensen’s theory: that different groups are predisposed to abstract versus concrete reasoning to different degrees, and to using cognitive heuristics versus figuring everything out for themselves from scratch. Kahneman describes heuristics as a source of bias and error, and indeed in the modern, increasingly abstract and statistically constructed world it no doubt often is. But as Gerd Gigenrezer has repeatedly pointed out, heuristics aren’t always wrong, they’re just ill suited to certain tasks:

As reflected in the amount of controversy, few areas in psychology have undergone such dramatic conceptual changes in the past decade as the emerging science of heuristics. Heuristics are efficient cognitive processes, conscious or unconscious, that ignore part of the information. Because using heuristics saves effort, the classical view has been that heuristic decisions imply greater errors than do “rational” decisions as defined by logic or statistical models. However, for many decisions, the assumptions of rational models are not met, and it is an empirical rather than an a priori issue how well cognitive heuristics function in an uncertain world. To answer both the descriptive question (“Which heuristics do people use in which situations?”) and the prescriptive question (“When should people rely on a given heuristic rather than a complex strategy to make better judgments?”), formal models are indispensable. We review research that tests formal models of heuristic inference, including in business organizations, health care, and legal institutions. This research indicates that (a) individuals and organizations often rely on simple heuristics in an adaptive way, and (b) ignoring part of the information can lead to more accurate judgments than weighting and adding all information, for instance for low predictability and small samples. The big future challenge is to develop a systematic theory of the building blocks of heuristics as well as the core capacities and environmental structures these exploit.

Does that mean that IQ isn’t a valid measure, doesn’t predict a lot of things (especially things very similar to IQ tests), and that disparities in certain types of accomplishment aren’t quite possibly here to stay? Of course not.

But it does mean that our baseline intuition- that who is dumb and who is smart depends on when it is and where you are– isn’t a total bust.

So sign me up for the Weak Voldemort View, and I’ll defend the Semi-Strong Voldemort View 80 percent of the way. But I think the jury is out on the Strong VV, and the human world remains a complex place, where a single number only gets you so far.

18 thoughts on “The Voldemort View: Weak, Semi-Strong, and Strong

  1. “concrete versus abstract” — the abstract thinker kids don’t like dancing.

    That reminds me of something I read long ago in, perhaps, Sports Illustrated about why professional athletes go broke on their investments: the reporter quoted a financial adviser as saying (roughly) that jocks had a “bias for the tangible.” He always talked up no-load mutual funds, but they always wanted to invest in stuff like carpet-cleaning businesses, which can be good businesses to own and run, but not to be an outside passive investor in.

    Liked by 1 person

    1. I was a pretty extreme nerd at school, and didn’t like dancing. It always felt weird – people would look at each other and move a bit but not too much, and I just felt so uncomfortable trying to join in.

      Then when I left school and grew up a bit I found out that if you forget about what everyone else is doing and dance really hard, it’s heaps of fun.

      Liked by 1 person

  2. Along the same lines, it’s interesting what a large number of top football players have gone on to be semi-decent movie/TV actors: OJ, Jim Brown, Merlin Olsen, Fred Dryer, Bubba Smith, Carl Weathers, Terry Crews, The Rock, Bernie Casey, Mark Harmon, etc. None of these guys were great actors, but they weren’t as terrible as, say, I’d be.

    This NFL to Hollywood pipeline has faded in recent years perhaps because there hasn’t been an NFL team in Los Angeles for 21 years. We’ll see if it starts up with the Rams moving back to town.

    Olsen explained that football players are good at being coached. The first evening he had been on a set, he watched the dailies and saw terrible he had been. So he demanded an acting coach. And he rapidly improved. Football players are good at imitation and adjusting their performances to take into account advice. Bigger budget entertainment productions have the resources to provide coaching for actors.

    It would be interesting to see if strong abilities of abstraction get in the way of this kind of imitation ability.

    Liked by 2 people

    1. This is pretty speculative, but there’s a hypothesis that many/most cases of autism are actually a result of cerebellar dysfunction. It’s counterintuitive, but if you think about it for a while it makes a lot of sense- autists have a lot of trouble integrating all the different inputs coming in, with costs for understanding language, relating to people, etc. Go to the other extreme (an NFL player) who is great at instantly integrating visual and auditory stimuli, and that person’s also going to be pretty good at integrating social stimuli.
      In any case, it would kind of make sense that the jock/nerd continuum is a lot about the balance between cerebrum functioning and cerebellar functioning.

      Liked by 2 people

  3. I think I’m mostly in agreement, but I do wonder whether “rote versus complex,” is really all that well differentiated from “concrete versus abstract” and “socially-embedded versus individually-achieved.”

    In practice, those things seem quite entangled. Since I’m a Thomist, I’m all for fine distinctions, but something makes me want to delve a little deeper into those contrasting pairs. Whatever it is isn’t coming to mind, but I’ll noodle on it a bit more.

    RE: your comment on the kid who could figure out what was wrong with the air conditioner, did you know the kid’s actual IQ score? I ask because my impressions are that grades are less and less g-loaded as time goes on, and that practical problem solving in my experience really does track well with what IQ measures. For example, in college I worked as a locksmith, instead of doing internships and undergraduate research like the other kids. I remember a conversation I had with one of the master locksmiths about how you had to be able to rotate all the parts in the lock around in your head and see how the mechanism fits together.

    They used to like to break in the new guys by showing them a mortise lock, asking if they understood it, and then dumping it out on the table and asking them to put it back together. Nobody was keeping track, but that sure as hell seemed like a g-loaded task to me.

    That being said, I’m actually pretty sympathetic to your argument as stated. I’ve spent a lot of time thinking about what exactly education and training means to people of all kinds of intellectual ability, and I’ve also had opportunity to put it into practice. I think you’re on to something.

    Liked by 1 person

    1. The kid I’m thinking of had incredible three dimensional visualization capabilities, but was a terrible reader and had trouble with math. He’d fix things all the time, down to figuring out why one teacher’s cell phone case was wearing out her battery by depressing one of the buttons, and could fix computers quite well; we brought him back for several years while he was in high school to help fix the computer lab, and he eventually (still? not sure) got paid by NYCDOE to do it. One question I have is whether predisposition to 3D vs. 2D processing is part of why girls now do so much better than boys in school.

      Liked by 3 people

      1. Hmm..that is pretty interesting. I would have guessed the kid had really good 3D visualization, which is why I brought up that locksmith example. I also suspect something like this is behind the current dominance of girls in school.


      2. Having worked for part of my career as a design engineer and an engineering manager, 3D visualization abilities appear to me to be: 1) very unevenly distributed; 2) very trainable in some; 3) and unrelated to academic ability and education. Some of the best designers I’ve worked with were high-school-only graduates, and some of the worst had strong academic engineering capabilities and advanced degrees, and were better suited for analytical engineering tasks.

        I spent the first couple of years of my career hunched over huge drawing boards throwing up relatively arbitrary section views of gas turbines in the process of designing major subsystems for the advanced cruise missile engine. The complexity of an off-axis part passing through a complex body of rotation, when you’re trying to detail that on a drawing board and make sure nothing runs into anything else, is substantial. Some of these designs I would work on for months, until I would literally be dreaming about them, and quite capable of rotating the various parts in my mind. But I didn’t get that skill from my mechanical engineering program at MIT — they had stopped teaching that decades earlier. It really was a 10,000 hour (probably more like 4,000) path to expertise. Complex 3d video games may teach similar skills with a bit less effort.

        Some of these visualization abilities appear orthogonal to verbal intelligence. There is a significant subgroup of engineers and physicists who are very intuitive (on technical issues), very strong on visualization and maths, and who seem almost incapable of complex written or verbal communication.

        Liked by 2 people

    2. My experience as a teacher (probably newer than Mr Toad) is that, while there are some kids who do badly on tests who ‘fix the air conditioners’ – I’ve met one who was really good at operating lab equipment and another who was unusually verbally expressive – they’re uncommon. I also wouldn’t be super confident making bets on the outcome if kids and those who do a little better on school tests if all took an IQ test.

      On the other hand, there’s one student who I’m very confident would get top marks out of all classes I’ve ever taught on an IQ test. He does particularly well on tests, but is also very expressive and capable of manipulating lab equipment.

      Liked by 1 person

  4. Interesting post and commentary. As always, Steve Sailer manages to tie together the most disparate and eclectic facts into a coherent explanation.

    Re: Voldemort views. Yes, I take the semi strong view. It gives nearly the same predictions as the Strong view (IQ is a great predictor of tons of things) with a less controversial explanation that I don’t have to self censor as much.

    It’s interesting to talk about this with smart friends of mine. One friend is going into a grad program higher education, is very smart, is familiar with psychometrics in the context of career placement– but when I brought up the BW gap that starts pretty early on in education, they argued that it was due to differences in summer enrichment and stuff like that.

    Not that I expect anyone who isn’t semi obsessed with psychometrics to really get IQ, but I’m always surprised by people who are smart, know part of the story of IQ or persistent gaps, but seem confident in other explanations.

    I often wonder how many people actually do hold a semi strong or even Strong view. I’ve got smart liberal friends (early 20’s, my age) who, when I make veiled references to Iq and group differences, seem to indicate they believe it too.

    Well, as soon as GWAS hits start rolling in in large numbers, it’s only a matter of time before an overzealous science journalist spills the story. Will be interesting but scary.

    Liked by 1 person

  5. Kahneman and Tversky were basically IQ scientists for the Israeli military according to Michael Lewis’s book about them. The Israeli military takes IQ testing very seriously, so it employs psychometricians like K & T.

    Liked by 2 people

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