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Jeff_H. comments on Why Are Individual IQ Differences OK? - Less Wrong
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What I find amazing is that no article I read actually quotes Watson as saying Africans have lower IQs. What he said was that he is “inherently gloomy about the prospect of Africa” because “all our social policies are based on the fact that their intelligence is the same as ours – whereas all the testing says not really.”
His claim was ONLY that Africans' intelligence is different than "ours."
Is there much doubt as to his meaning? Perhaps not, but I should think on this blog we would not commit the sin of assuming too much.
First, I want to say this: I have no idea whether his claim that Africans got a lower IQ score on the test in question is true or false. I hope it is false. There's a possible explanation that is totally in support of the Africans, EVEN if the claim was true. Here it is:
IQ tests are culturally biased. If the test asks "How do you use a teacup?" a British person will be likely to know the answer - a lot of them use teacups daily. Do Africans use teacups every day? Maybe they'll bomb on the teacup question because they drink their tea from bowls as with Japanese matcha tea, or from gourds as with yerba mate tea. If you ask them "Is a rattlesnake dangerous?" that question is irrelevant to them. They have boa constrictors, but not rattlesnakes.
There are tests that are designed to prevent these differences from influencing your score. They're called "culture fair tests". Nobody here has specified whether a culture fair test was used (I searched the page).
If IQ tests are 'culturally biased', then we would expect the highest scoring group to share the same culture as the test writers. The highest scoring group does not share the same culture as the test writers (for instance, East Asians score higher than White Americans). This seems to be strong evidence that IQ tests are not 'culturally biased'.
Ok. Interesting point, but did this group of Asians take English language courses at school? Do they have knowledge of American culture via entertainment channels? Perhaps the Africans who allegedly got low scores were people who grew up living in tribes in the wild, and only came into the city where they ended up getting tested recently. I met a person whose mother fell in love with an African tribesman and I read her memoir on the experience - it wasn't long ago that she met him, a decade or two maybe. There may be a large proportion of people in Africa who literally grew up in a jungle.
In addition to straight up single-culture cultural differences, there are also variations from one culture to the next between which foreign cultures they've been exposed to (if any) and enjoy. Some cultures seek to limit their exposure to the outside (North Korea) while in others, the ideal is to embrace them (USA). For instance, here, there are many fans of Asian culture - think anime, Japanese video games and lovers of Thai food. Do they have a multicultural atmosphere like that in Africa? Sure there are American missionaries around who probably bring teacups and the like, but there's a giant difference between occasionally seeing some white people with some cups they didn't tell you anything about because they were too busy feeding starving children versus being taught their language in a class and spending time absorbing culture from their entertainment products.
Not only that, but differences between one IQ test and another could be gigantic when it comes to how many culture-dependent questions are in them. If you haven't specifically controlled for that during test design, that would be completely random. Maybe the Asians just so happened to get the test that had fewer cultural questions on it, and the Africans got one that was thoroughly based on many obscure pieces of cultural knowledge.
What we really need to be asking here is this:
Has anyone done a culture fair test for multiple different countries, using the exact same test with each one, and controlled for factors like whether the people being tested were schooled as children, whether they ever experienced starvation (that can cause brain damage) and any other important things?
Only if all the factors are controlled for would we have relevant data.
If I'm not mistaken, the most widely used IQ test is the Raven's Progressive Matrices. How is taking English lessons or having been infected with Anglophonic memes going to help you guess which shape goes in the white box?:
I wouldn't rule out the possibility. There is an environmental influence on even more fundamental visual perception and so could well be related differences here. Further, past exposure to tests in general and tests of the 'complete the pattern' variety is going to bring up a cache of typical things that a test designer is likely to include. It is more or less a habit for me when looking at such a problem to test if it is simple rotation (by either a constant amount or an amount that increases by a constant amount, depending on the level of the test).
I seem to recall that the Ponzo illusion doesn't work among cultures not accustomed to visual art using perspective.
(Edited to replace ASCII art with a link to Wikipedia.)
I think it might be wiser to link to an image. Wikipedia's article on the Ponzo illusion appears to be talking about the same thing.
Thank you. I had no idea what the name of that illusion was.
That's a pet peeve of mine: that illusion belongs to class of illusions of the form, "If you saw this in real life, your perception would be right. But it's a 2D picture, so you're wrong."
It's exactly the same as taking this standard optical illusion, and instead of claiming the A/B squares are the same color, saying "This image has no squares. Verify it for yourself!" (i.e. in the plane of the image, nothing makes a square, but it's understood to represent a perspective image of squares)
Nothing wrong with exploring these -- they're very informative about how our perceptual system works -- but please understand what's going on.
I can see, then, how a culture not expecting perspective images, can interpret them as flat and not fall prey to these illusions.
Another thing I thought about is that there weren't that many straight lines and right angles in the ancestral environment, so i think it's likely that the module in the brain for "getting" perspective doesn't come from a blueprint in the DNA but rather it arises in response to stimuli in the early life. If this is right, there might be differences between people who spent their early childhood in rural vs urban environments.
An old psychology professor of mine once gave an anecdote of a tiger that was kept in a cylindrical room during its early phases of development. It grew up to have a warped sense of spatial awareness and was unable to function properly for the most part. I don't know the details surrounding the story, so I can't confirm it right now, but I'll see if I can find the study (assuming it does exist).
We both underestimated how inaccurate cultural differences can make an IQ score, I think.
I have two rebuttals specific to your assertion that knowing English shouldn't affect your ability to solve IQ test puzzles, but I also thought about this more and realized that even a culture fair test probably cannot compensate for the differences between the three groups of people we're discussing, so I gave a couple examples for that, too.
First: How are you supposed to understand the question that goes with the puzzle if you don't know how to read English well? Without that question "Which shape goes in the white box?" there is little hope of interpreting the puzzle correctly, let alone filling it out. This is an IQ test, and the questions are sometimes written in a way that makes them tricky to understand completely. IQ tests may demand a high reading level. If all you've got is broken English, reading and comprehending questions like these might feel like you're doing something as hard as applying Bayesian probability to statistics.
IQ tests are also frequently written by people who don't consider all possible ways of interpreting the question. If you were not constantly exposed to academic conventions, you are likely to interpret the questions in a different way without realizing it. Look up the difference between "divergent intelligence" and "convergent intelligence" if you don't believe me. That's a big problem for people with divergent minds - even ones who have been schooled - they see all these options that other people don't (essentially, they're creative) and they tend to get lower IQ scores for no reason other than that they did not interpret the questions and answers in a convention manner. A professional developmental psychologist may provide a creativity test to these people, and if they score significantly higher than average on the creativity test, they'll actually adjust the person's IQ score upward accordingly.
Now for our underestimation of cultural differences: I think you're really underestimating the amount of difference it can make to the human mind to grow up in a completely uncivilized environment. These children (specifically the Masai tribe I read the book about) are literally growing up stealing cow's blood from the adult's tubs for their survival (it's a staple food for some) and as a game, they dare each other to challenge wild animals. They're not sitting there day after day, like you and I have been, looking at pieces of paper. Their lives are completely different, and this most likely makes a profound difference in what kinds of processing their brains develop.
For example, there's a lot of controversy over whether ADD is a disease, or if children just aren't meant to be sitting there in classrooms. Some theorize that ADD is extremely useful for your survival if you live in a jungle. You have to be aware of your entire environment the whole time. If the kids are growing up surrounded by boa constrictors and other dangerous animals, they have to REALLY develop their ability for paying attention to every little sound and movement. This is the opposite of what the schooling environment will do - force you to learn how to focus for long periods of time on little pieces of paper, doing thinking work, while blocking out any noise or thought you have that's unrelated. Concentration is a skill, no?
That's just one difference. There are others.
For instance, have you ever heard it's important to teach math in school, not because everybody needs high level math itself, but because doing the type of intellectual rigors involved in mathematical calculating will boost reasoning in general?
If you were tossed a machine gun at the age of 6 and told to shoot or die, you're totally not going to spend any time on math. And some of them were. (I learned that in a Ted talk video).
The Chinese people that were tested, to contrast, may have spent a lot of time as children working in sweatshops making small items or doing fine motor skill work like making toys and sewing. They've probably spent a lot of time developing their ability to concentrate - way more than would be demanded of the average American kid (they're working 16 hour days...) and furthermore, constructing these products takes a bit of reasoning.
Don't underestimate the difference that culture can make to an IQ score. Now that I've thought about this, I'm not even sure a culture fair test can compensate for these differences. It probably only works if you compare people with a similar upbringing. Comparing jungle survivors vs. sweatshop laborers vs. schooled Americans is probably going to yield different results no matter how you design an IQ test.
My measured Ravens IQ jumped a good ten points after the experience of taking a few IQ tests, because I got a sense for the thought patterns of the test makers. This indicates that you can learn how to do better on these tests, which further suggests that cultural knowledge might help you learn it faster.
A westerner customarily reads from left to right, and then goes down one line. Note how the incomplete square is also the last square that the Westerner's eye would consider...only after seeing all the relevant information would the Westerner consider the empty square.
A westerner also frequently uses the concept of clockwise and anticlockwise. The black square progresses in a neatly clockwise fashion for each shape as it is viewed by the western gaze. Thanks to the bottom third line breaking the top left/top right/bottom left pattern, one must use clockwise/anticlockwise notions to complete the pattern.
A westerner has also been taught about division using pie charts, and each of these shapes are divided neatly into fourths. Add to this a passing familiarity with grids, the idea that tests are important in the first place...you get the picture.
To get some sense of how difficult this task would be for, say, an illiterate hunter gatherer, try rotating the image 45 degrees counterclockwise and refrain from using your prior knowledge of the correct reading frame to complete the pattern. Suddenly, it is a lot harder, isn't it?
If the first two shapes on the bottom are diamonds, why is the third shape a square?
I think that's meant as a field where you'd draw in the shape, diamond and all.
And what makes you sure of that? It even looks like the outline for the three boxes along the top.
Our cultural assumptions are perhaps more subtle than the average person thinks.
Ugh, visual shape processing. You grow up with that sorts of shapes (and patterns, and consecutive patterns that are regular, and so on), Africans don't. You grow up with everything in left to right order or right to left order, they don't.
What do you think goes on formally (mathematically) with the correct answer, anyway?
The correct answer is the one where the whole thing with the square filled in can be least complexly represented with most culturally common operations (mirrorings, rotations, superpositions, etc) done on orderings of the squares. You have a penalty for each operation (more for less common operations), you add those scores for the whole set of relations, you pick the smallest. That's roughly what a programming contest solution for that sort of thing would look like (leaving aside the question of hardcoding or inferring the patterns and their penalties themselves).
Yes, the operations are in some sense fundamental, but you haven't reinvented them, you learned them, from when you were categorizing visual input as a child.
As an IQ test, it has two parts: the visual input you are exposed to as a child, and the matrices themselves. Since we're all acquiring a sufficient training dataset, it works just fine as an IQ test for us.
edit: Also, try replacing the square to fill in with a circle, and see how many people will get that wrong. Empty box to fill in is a cultural concept. A child unused to this will think they need to use that box as part of the answer.
One big cultural difference might be how seriously tests are viewed, and how much practice people get at taking them.
East Asians in America or East Asians in East Asia?
The former, IIRC.
Both, actually.
Average IQ
Uh, two to three points is noise. Edit: er, possibly. What was the sample size?
In any case, it is clear evidence against the 'cultural bias' hypothesis.
Richard Lynn, Race Differences in Intelligence (2006) refers to a study with n = ~2000 for whites in US getting IQ 103 and a study with n = ~1000 (plus several with n = ~500) for Japanese in Japan getting IQ 105.
This assumes that if a test is culture biased, it must be biased in favor of the culture as a whole. A test can be culture biased by hyper-valuing a set of skills prominent in one culture, even if that skill set is stronger in some other culture. If IQ is biased, say, toward "academic culture," even though this is a feature of "white U.S. culture" it may be even more a part of East Asian culture.
What I think your argument shows is that the tests aren't intentionally biased in favor of one culture specifically. In fact, the studies of early IQ testing shows there was intentional bias (not so much today), but rather than being in favor of the dominant culture, it was against the cultures of particular immigrants. (I'm speaking of the Army Alpha tests.)
The best explanation for this I've heard is that there is a certain mindset (the writer refereed to it as a "modern mindset") that is uncorrelated with intelligence, but that allows you to do better on intelligence tests. As evidence for this, he used the fact that right here in America, test scores have gone up over the past several decades. This clearly isn't caused by some genetic change, so the most likely explanation is cultural change.
When people say that the IQ tests are culturally biased, that doesn't necessarily mean that "white Americans" have the biggest advantage, it just means that IQ tests are measuring at least two separate qualities; one which is "intelligence", and the other being some facet of the culture.
There are cultural factors that might give someone in China and advantage over someone in America on an IQ test. One of the simplest explanations I've heard is that the Chinese numbering system is easier to learn and more intuitive to do simple addition and subtraction with. While most number in English have a regular pattern that makes them easy to understand and to work with, (twenty-one, fourty-three are said in "tens then ones" form), the numbers right after ten don't follow this pattern in English (eleven, twelve, thirteen, fourteen, fifteen). This makes them more difficult for a child who is first learning his numbers to do so, and makes them slightly more difficult to work with on a cognitive level (it's intuitive to add fourty-one and twenty-two and get sixty-three, since those numbers are in tens-then-ones form; it's less intuitive to learn do that with eleven or thirteen).
Anyway, that's just a simple example of the kind of cultural difference you won't even notice but might give one culture a small cognitive or learning advantage over another that has nothing to do with genetics.
Is that actually more likely than environmental change?
It might be caused by a genetic change. Populations are becoming less inbred. This would be expected to raise IQs, though I don't know what the expected magnitude of change is.
It's been claimed ("Resolving the IQ paradox: Heterosis as a cause of the Flynn effect and other trends") that hybrid vigor/heterosis may help the Flynn effect, but this is not a popular explanation since it doesn't explain the pattern of gains on IQ tests or the apparent size of the Flynn effect. I mean, inbreeding depression alone costs much less than Flynn, so it's hard to imagine that outbreeding could be so valuable.
I suspect that my characteristics are partly due to hybrid vigor, as are my sister's. It's not so much "neg (inbreeding depression)" but more of a "when pooling both the strengths and weaknesses of two respective gene pools, the strengths of having access to more 'highly beneficial' genes tend to outweigh the weaknesses of being struck with 'detrimental genes' from a different region". So hybrid vigor isn't necessarily antisymmetrical (I doubt it is) to inbreeding depression. Beneficial/detrimental being relative to the current stage of human civilization in general, and your culture in particular, of course. Example: propensity for thalassemia, good once, bad now.
Interesting. Can you elaborate? What are the patterns exactly, and how do we know what inbreeding depression costs? From recent studies of inbred individuals? I'd be very surprised if it was the only cause of the gain in IQs, but as your reference says, it represents a pretty decent hypothesis for at least some of the effect.
Being confined to the subscales that look like pattern-matching and analogies, IIRC; I'm not sure which paper I get this from, but it seems Jensen does at least make this claim in http://www.charlesdarwinresearch.org/2010%20Editorial%20for%20Intelligence.pdf and in some citations in http://menghusblog.wordpress.com/2013/06/21/explanation-behind-the-non-g-gains-in-the-flynn-effect-introducing-the-measurement-invariance-model/ so there's some starting points at least.
Yes, that's how one would do it. The usual reference is to a study of Japanese cousin-marriages back in the '50s or so where IIRC the estimate was <5 IQ points, but there's been research since then, of course; a google for 'inbreeding depression intelligence' should bring some research to light.
Environmental change is certainly possible. For example, the amount of lead the average person gets from the environment has been slowly falling for several decades now. Better pre-natal care, and better education about the effects of consuming even small amounts of alcohol during pregnancy, might also be factors.
I think that cultural change is probably the biggest single cause of the Flynn effect, though. Computer use, increased practice taking standardized tests in childhood, ect. Which doesn't necessarily mean that they're smarter, just that they'd better at taking IQ tests.
I'm pretty sure IQ tests don't ask questions like that. They're supposed to measure intelligence, not knowledge (at least in principle¹), and it's obvious that even a very smart person couldn't possibly figure out whether rattlesnakes are dangerous while taking the test, short of knowing that beforehand.
I took an IQ test that had a bunch of "what's wrong with this picture" items in one section. I don't remember any of the questions but the last one - the last one required me to know that there wasn't any air on the moon.
Well, a sufficiently intelligent person could guess that the moon is likely too small to have strong enough grav[realizes that Alicorn is looking at him in a weird way]... Just kidding. :-)
That was obviously a bad test.
There is a theory about how IQ tests should be designed. Most of the complaints in this discussion about why some IQ tests are not fair, are already known, and probably have been known for decades.
Of course it does not prevent people from ignoring those suggestions and making their own mistaken "IQ tests" anyway (especially if there is money and status to gain by doing so). Just like any amount of medical research cannot prevent people from making and selling homeopathics.
Okay, my examples sucked, but the general principle that one's abilities with reading and English will make a big difference on a written and/or English IQ test still holds. I made that point a lot better in a different comment. http://lesswrong.com/lw/kk/why_are_individual_iq_differences_ok/776g
Interesting. [searches Google for "crystallized intelligence"]
Cite please. This is a completely novel claim to me, one I routinely see problems with (eg. a few days ago reading a SMPY review mentioning a 13-fold gender imbalance in extremely high SAT math scores while tests of fluid intelligence show little or no such asymmetry). I find it very hard to believe that matrix tests predict mathematics success and little else.
If you are trying to express some reasonable position like "IQ tests (which include subtests covering a variety of crystallized materials as well as fluid intelligence measures) will have some incremental predictive validity for various activities or life outcomes over an IQ test (which is just a measure of fluid intelligence)", then perhaps one could agree. But your current absolutist statements seem to be endorsing some other position...
Are you challenging me to find a single study using a matrix test which predicts to any degree some metric other than math success, such as income or employment or highest attained degree, and that's it? Are you sure? Because your following restatement agrees that matrix scores can be predictive outside math.
I think we have different views on what is "valuable" (eg. is a matrix test faster and easier to administer than your combo of other factors? Then it could be valuable even if it's not quite as good a predictor), but your stronger position does not seem obviously wrong to me, so I won't object to it.
Look at ravens progressive matrices, these are as far from relying on culture as you can get- they are too abstract and tend to show reasonable distributions of results in all groups. They also show poor results for some groups, including africans.
This comment makes my point on this better than the one above did: http://lesswrong.com/lw/kk/why_are_individual_iq_differences_ok/776g
Regardless of whether or not it is true it is not supported by the rest of the paragraph. That explains a way in which some arbitrary test which clearly is different in nature to an IQ test could in principle be culturally biased.
(The final paragraph does constitute support of the claim, in as much as the existence of a culture fair test implies an authority sees a need for it.)
That's a valid criticism, so I explained a lot better here: http://lesswrong.com/lw/kk/why_are_individual_iq_differences_ok/776g
If you're interested in the topic, Lynn & Vanhanen have released a new book on the dataset, Intelligence: A Unifying Construct for the Social Sciences, at least some of whose chapters seem relevant to the question of the validity of the scores. (I only just downloaded it and so haven't read said chapters. EDIT: excerpts)
I'd note in passing that a culture-loaded test could be perfectly useful in ranking people within a different culture, for the same reason that crystallized intelligence can be used to predict fluid intelligence: if the smarter people are more likely to remember something after just 1 or 2 exposures, and everyone is rarely exposed to the foreign culture, then when you test people on the foreign culture, you'll wind up constructing a ranking which looks a lot like what a 'fair' IQ test would have given you. (Imagine you're an inner city black: you may see or hear of yachts just a handful of times in your life, as would all your confreres; the ones most likely to remember what a 'yacht' is when that infamous example comes up, are... going to be the smart ones who can remember obscure trivia like what white people mean by 'yacht'. The occasional homeboy obsessed with boats but not terribly smart will add noise to the ranking by knowing all about yachts, but over the whole inner-city population, the ranking still works.)
I finally got a chance to give that a look, skimmed various areas to get an idea of what's in there. What I reallly want is a chart that looks like this:
Poverty
War
Sweatshop
Schooling
Racial Attitude
Where all the boxes for intersections have the average IQ score, and there are, of course, more columns to account for all the things that might have an effect. Lead paint exposure, crack epidemics, etc.
Without that, we're never going to have even the slightest clue. Even with it, we have to ask "Which was the chicken and which was the egg".
Maybe Africa is smarter despite the score... I just realized there's another reason why a chart like the above wouldn't answer this question:
We have to ask "Might being under really tough selection pressures actually make a population smarter than they appear?"
First half of my point: Say we accounted for all the details and we discovered that a particular group had been through it all. You have to wonder how the hell they survived. More intelligent people more likely to survive hard circumstances, aren't they? Maybe it depends which circumstances. But my thought is that a population of people that's been surviving something really, really hard might end up having it's genes influenced by natural selection, so that there are way more bright people. Second half of my point:
Combine this with another thing that affects IQ and you'll see where I'm going with this:
If a person has depression, for instance, that can lower their IQ score 30 points until the episode of depression ends. They might have a lot of IQ points in there that we can't see because their IQs are suppressed by stress - not permanently damaged, just suppressed.
If stress can lower your score substantially, then a population might require a larger reserve of intelligence if it is going through something awful. What if you're depressed AND at war AND survived starvation, AND weren't schooled, etc. To be able to accomplish an IQ score of even 85 might take a genius after going through all that. So, they could have a population of geniuses over there, and we wouldn't know. Because we, over here in civilized land, have no idea where to even begin guessing what AMOUNT of IQ suppression a combination of factors so terrible would have, especially because they'd probably multiply each other.
So, if we looked at a population that had been through a heck of a lot, and they don't score very well, does that mean that they're dumb (as in born that way, or permanently stuck there), or that they are, in fact, super smart (say, IQ 140) but that the EXPRESSION of that is suppressed because they're so ridiculously stressed out?
So, we could look at this another way: What IQ would it take to go through all the hell an African has gone through and survive it?
Why would you think this? Intelligence is metabolically expensive, and pays off only in the long run (consider how much of a life you can 'waste' getting an education). Putting people into a resource-pressured poor quality environment would seem to select for more immediately useful traits like aggression or growing up very quickly (and hence, investing in poorer quality body parts or less of them, like being shorter).
If there were a lot of resources on average but the environment fluctuated a lot, then there might be evolutionary pressure for intelligence: but this does not describe Africa too well and better describes very northern countries like Scandinavia where you can freeze to death but agriculture or fishing etc still yield lots of food. The book does discuss this theory and run some regressions in its favor. (I've always been a little dubious: it seems to me that it largely depends on European countries for most of its value...)
Gifted babies do things sooner - that's how early it shows up. Gifted children can learn to walk sooner, talk sooner, climb sooner, have rational thoughts sooner, etc. I'm not talking about marginally sooner. I'm talking about huge gaps like 1/3 sooner or 3 times sooner, and sometimes even 12 times sooner (William Sidis).
Gifted children tend to be bigger, not smaller - they develop faster. All these things would certainly give them an edge over the other children. They do grow up faster - otherwise what else describes child prodigies? They've reached an adult level of skill as a child. That does happen, you know.
Gifted people tend to be emotionally intense - and of course they may express that in any number of directions (sadness, happiness, anger) which lends itself to the idea that some portion of the gifted population may be easier to provoke to the point of aggression.
And there are different kinds of gifts, different sources of giftedness. Some gifted people only need three hours of sleep, for instance. I've met several bright people that require only three hours a night. That's five extra hours every day. Imagine that all your days are 1/3 longer, and how much of an advantage it would be.
What are these "resources" you keep mentioning? It's not like gifted children eat two elephants a week. They eat normal food.
Do you happen to remember the area of the book dealing with this theory?
All of your points may be true, but are not especially relevant. Philippe Rushton makes much hay in his lifecycle theory of how black kids grow up faster than white kids and much faster than East Asian kids, but that doesn't mean they're destined for genius any more than chimp infants growing up much faster than human infants means anything.
Fats, protein, calories, time-investment, sleep. Feel free to look through http://www.gwern.net/Drug%20heuristics for those (the sleep one IIRC is from Ericsson).
How do you know how much they eat? Have you weighed out their every meal and snack? Just a few hundred calories made the difference between life and death in Nazi concentration camps; how much more so in famines or droughts? Your intuitions from a fat Western First World environment are not very useful in this discussion.
I have, actually, with modafinil. It's not as impressive as one might think; if you weren't being productive with your original waking hours, getting some more is not necessarily going to revolutionize your life. Further, we know that sleep deficits are one of those things that are easy to fool yourself about: the chronically sleep-derived are deluded about whether they are paying any mental price for the sleep deprivation.
There are different speeds at which people grow up, it's not boolean. There are different levels of giftedness. Some are so gifted as to be called geniuses, some are more along the lines of talented, and there are plenty of people in between.
Food: Now that you've said "a few hundred calories makes a difference", I see that this could be a potential setback for them. That was a good point. I don't know whether they eat a bit more or less, though I know that they can experience reactive hypoglycemia if they don't space and balance their meals properly to avoid blood sugar crashes.
Sleep: Gifted children are more likely to need either more or less sleep than average. So far, I've met a bunch of gifted people that need less sleep, and none that need more. If sleep were a survival factor, then the gifted people who need less of it would theoretically just be more populous than the ones who need more. Obviously, the longer sleepers theoretically would not prevent shorter sleepers from surviving better.
It's not 100% clear to me whether brilliant people who sleep 3 hours a night experience sleep deprivation symptoms. However, when you're looking at something as extreme as a 5 hour difference, you'd think the person would unravel very quickly, if they needed those 5 hours. If they're paying a price for it, it's certainly not nearly as bad as the price an ordinary person would pay. A normal person would probably devolve into schizophrenia after a couple weeks of that. But these guys seemed bright and rational.
Einstein and Feynman didn't start to talk until they were 3.
Huh. I didn't know that. My parents thought I was deaf until one day I started talking - in full and coherent sentences.
How common is that?
This old Language Log post discusses some fictional, real and apocryphal cases.
I couldn't give a figure for it but it is a common enough occurrence that my Asperger's Syndrome textbook notes it as a possible outcome.
I had originally read that on the WIkipedia article about Feynman, which links to http://en.wikipedia.org/wiki/Language_delay, which cites http://pinker.wjh.harvard.edu/articles/media/1999_06_24_newyorktimes.html (which I haven't read yet, but I'm going to).
One example: the population is Ashkenazi jews, and the environment is the racist world we live in. It's not clear how much is cultural and how much is genetic, though.
What? If you have in mind things like the Holocaust, remember that the causation goes the other way around. Success breeds resentment, rather than resentment breeding success. Jews are a market-dominant minority, and across the world market-dominant minorities are subject to violence and resentment.
Jewish intelligence is likely due to their particular economic and social position in the middle ages, where they had long-range trust networks that facilitated moneylending and trade, as well as a religious prohibition from marrying with the locals that meant they would specialize more towards their ecological niche. (And it seems likely that they picked that niche because it was a particularly pleasant one, not that they were forced into it by oppression.)
Thanks, it's good to know about market-dominant minorities.
I'm not sure what to do with this information...it seems to accurately describe the situation but is also very disturbing, for two reasons: First, it sounds like blaming the Jews, in that if they were a model (politically-weak) minority instead of a market-dominant minority they wouldn't have been scapegoated for Germany's economic problems, which is terrible (but I'm pretty sure you just are trying to describe the real world, with no value judgments whatsoever meant). Second, I am apparently one of the oppressors of today. Most Americans don't think much about the poor people who make the stuff they buy, or who get exploded by the weapons their military develops.
"Is" doesn't lead to "should", and there's no legal obligation to seek out opportunities to save lives, and I don't have enough power now to make a meaningful difference, but it's really hard to say "I don't care what other people think; I'm going to do what I want!", when every normal American day I burn enough money to support a few impoverished families. If I gave up some luxuries, I could save peoples' lives, but if I give in to that it means the end of my dreams, and would not necessarily do the most good. Most people choose not to think about these things.
Is it time to jump off the slippery slope? I falsely equate being selfish with being evil, because it feels like the cost of embracing selfishness is, to quote Steven Pressfield, to "wind up alone, in the cold void of starry space, with nothing and no one to hold on to." But, being unselfish ends with my death with nothing meaningful changed, and refusing to choose, while easy, is a non-option. I need to not die, and to know the meaning of life, and I want to help others to the extent possible. Owning my place in the real world is painful but seeking oblivion through distracted and unhealthy living, because of my unwillingness to own my place as a subordinate fiend, is worse.
The Ashkenazi Jews are still a small population, though. And intelligence may be an reproductive advantage in their niche, but that's only one niche. If you don't like the example of the Holocaust, consider the Khmer Rouge going after anyone who seemed intelligent.
The Khmer Rouge were dramatic, but I'd bet money that simpler forces have played a greater role in the evolution of intelligence since the Neolithic. As you say upthread, intelligence is metabolically expensive, and it seems likely that it shows some fairly steep diminishing returns in a subsistence farming environment -- particularly since its gains there are distributed over large populations. If a mutation gives you a chance of dying in a childhood famine and a much smaller chance of coming up with an agricultural innovation that might save your kids (and the rest of your village, but your mutation doesn't care) from dying of childhood famine, it's no advantage from a gene-centered point of view.
(On the other hand, if being good at Torah study is sexy in your subculture, then sexual selection might make up the difference.)
That's true comparing chimps to humans. I am not sure that's true comparing an IQ70 human to an IQ130 human.
I have no idea what your chart would mean. The book supplies tons of regressions if you want some sort of prediction on an individual level (and cites many individual studies which may be more useful than cross-national regressions), so you can't complain data is lacking.
Where did this explanation come from? The way you present it, it's as if you looked for this explanation in order to save a belief about the intelligence of Africans.
I have seen a few IQ tests, and none of them contain questions remotely like this. This imaginary IQ test question seems to have been invented as fictional evidence to support the explanation.
IQ tests these days are typically "culture-fair", by which is meant that the questions are non-verbal and non-pictorial. At least, that is what is usually meant, although on googling for "culture-fair", I did notice the occasional assumption that a test that gives different average scores to people from different cultures is ispo facto not culture-fair, making equality of IQ between cultures an axiom instead of an observation.
Even without looking at cultural unfairness in the tests themselves, it's very hard to tell apart genetic factors from nurture.
Be it within the US (or Europe) or between US/Europe and Africa, there is a strong correlation between skin color and economical status. Lower economical status means lower quality food, higher chance of living in old buildings using lead-based paint, usually poorer quality shcools, ... which all affect the developement of the brain.
Is there any study done for example on the IQ of black children raised from a very young age in middle-class foster families, compared to whilte children raised in similar conditions ? Even then we couldn't rule our non-genetic factors that affected pregnancy (like bad food quality or drug/alcohol use during pregnancy), but it would be more significant to claim that there is a significant genetic difference.
Even that wouldn't work. Here's why:
Read about Jane Elliot's brown eyes, blue eyes experiment. Cliff notes version: A school teacher tells her class that the brown eyed kids are better than the blue eyed kids, puts collars on the blue eyed kids, and sees what happens. Very, very quickly, they take on these oppressor vs. victim roles. Suddenly, she's noticing things like the blue-eyed children who used to be smart couldn't perform well. Brown-eyed kids were spelling words she knew they couldn't spell.
Simply being a black child in a white-dominant classroom is enough to potentially throw those kids off on the tests. Could this be a problem for a predominantly black school in a white-dominant country? Or a predominantly black country in a white-dominant world? It is argued that America is not a white-dominant country and that's true if you look at the population statistics. But that doesn't mean everyone's updated their attitudes or that the social structures have really changed. :/
One interesting thing I want to note here is that I have read that Chinese people feel a sense of pride about being "the first people." I don't know whether that is a common attitude in China, but IF it is, and IF these IQ tests are actually accurate (which I have already stated some serious criticisms about) perhaps the difference is the way that the races perceive their lot in the world.
Also, I hate to do this to you because if I were on the receiving end I would feel really bad, but I can't not say it now that I've seen it:
Why do we have to stick to comparing black foster kids with white foster kids, as if there are no black children in middle class families to research? Michael Jordan, for instance, made it well beyond the middle class. I've seen black people working middle class jobs, and met a black guy recently who makes a lot of money working in IT. It's not like they aren't out there.
I hope you don't take it too badly... we all come here because we want to remove our bias. That's a respectable goal. If you see any of mine let me know. (:
I think this is the most interesting sentence in the whole discussion.
Let's be clear. Racial groupings are really very significant pieces of evidence. There's huge amounts of genetics that correlates, huge amounts of culture that correlates, huge amounts of wider environment that correlates. It would be frankly astonishing if things like IQ, reaction time, hight, life expectancy, and rates of disease didn't also correlate.
So, we ought to expect to see a correlation, and in fact a whole bunch of studies say we do. ... And then those studies are put under far more than average pressure. See people below wanting to dismiss Raven's Progressive Matrices as culturally biased. Why on earth do we want there to be no such correlation with IQ.
We're very happy to say there's a correlation between race and hight, between race and life expectancy, between race and disease, between race and income. Why not race and IQ? Why do we want that to be false?
Well, there's a correlation between race and height, too, no doubt, but such correlation is utterly insignificant comparing to variance within either race - you don't say whites are taller or blacks are taller, there's very short black populations and very tall ones, and ditto for the whites whose variance is smaller.
The quantitative differences make a qualitative difference here.
Racists believe the correlation to be of greater significance than that of correlation between the height and intelligence. Based on fairly poor evidence - Raven's matrices are not this culture fair, they're culture fair in the sense that you can test British, Germans, French, Russian, and Chinese and Japanese with it, not in the sense that you can go and test some tribe that doesn't do much arithmetic nor is exposed to similar visual stimuli.
By the way given the diversity of blacks it would be utterly surprising if there is not a single ethnicity there with an average IQ greater than 100, as well as IQ with greater or smaller variance. (I would expect blacks to have larger variance than whites because they're plain more diverse, and mixed to have greater variance still)
Then the "rational" racists also object to use or even the existence of correlation between such racism and intelligence, conscientiousness, education, and other factors.
Notice I said nothing at all about racism or our policy responses to race. Of course intra-group variation is more important, that's obvious and applies to height too. This much is well known and irrelevant to my point.
The thing I'm interested here is why it's commonly accepted that there ought (in a strong moral sense) to be no correlation. Not our response to the actual existence of that correlation.
I am not aware of any test of pattern recognition that is more culture fair than Raven's, but would love to hear of one if you're familiar with one, and I would be rightfully suspicious of the intellectual capabilities of a tribe that has not invented arithmetic.
I'm not aware of many ethnicity-level studies; I think the best we have are nationality-level studies. The highest country mean in all of Africa that I'm aware of is Morocco, with 85.
It's an interesting and very common form of an entirely irrational argument. (Hypothetical) absence of a better test in no way implies that it is a good enough test for a select purpose. Especially when no one really tried to quantify the error you might get.
I said, "doesn't do much arithmetic". You can look at the whites 1000 or 2000 years ago and vast majority don't do much arithmetic. "Haven't invented arithmetic" is your invention.
I prefer quantitative arguments to qualitative arguments; relatedly, I prefer certainty as a number to certainty as a word. I think it's better to make the most of mediocre data (and figure out which additional data is highest EV) than to throw out the best data available.
It is not true that people haven't tried to quantify the error they might get; this is actually a major concern of psychometricians. They've figured out several ways that a test can go wrong, and have come up with quantitative measures on how much those seem to have happened. For example, a problem with WWI-era IQ tests was that the modal number of correct questions was 0, which suggests that a large number of test-takers did not understand the instructions, which dropped the uncorrected mean significantly. Now they look for this problem.
For example, here's a paper about Raven's in Africa, which goes through the various ways that Raven's could underestimate African intelligence. It's full of quantative statements like "the correlation with other intellectual tests is generally about .6 in Western studies, but is .33 in African studies, suggesting it is less g-loaded for Africans."*
If you wanted, you could figure out what an individual Raven's score of 80 implies for any other cognitive test in Westerners and Africans respectively. Like any Bayesian exercise, this relies pretty heavily on the priors you choose: if you assume the score is accurate but not precise, then you have a mean centered on 80 but a difference variance for the two groups, with a larger African variance because your test is less precise. If you assume both groups have the Western mean, then the regression to the mean (i.e. upwards) is higher for the African than the Westerner, again because the test was less precise.
*I should point out that there are other, competing interpretations of this finding, and it seems that the correlation is lower for the more rural and less educated, suggesting the left half of Fig 4 is due to culture. But from the studies on the right half of Fig 4, we would end up with an estimate for African intelligence given Western culture that's about 80-85, which is a bit lower than African American intelligence.
I was thinking of anumeric tribes, which are rare enough that we're not quite sure whether or not they exist. But many tribes seem at least partially anumeric, and I would be surprised if that were not predictive of the mean IQ of people currently in the tribe (setting aside the question of 'genetic IQ capability').
That most Romans did not do much arithmetic over the course of their lives doesn't say all that much about their ability to do arithmetic or their general intellectual capability; most modern Americans don't do much arithmetic (and, actually, they probably do less because they have more machines to do it for them).
Culture and environment are not race. Therefore, if you're studying race, those influences should be taken out of your scientific experiment. It's extremely difficult to remove things like culture and environment from a study on IQ. The fact that so much is correlated with it doesn't mean the results of studies intended to determine racial differences are significant so much as it means they're a tangled mess of cause and effect which we likely haven't sorted out adequately.
A. We don't want black people to suffer needlessly.
B. We don't want to encourage ourselves and others to be prejudiced against people when, regardless of what the average African's IQ is, it is still both logically incorrect (hasty generalization) and ethically wrong to prejudge individual Africans. However, knowing how humans behave, we figure that if people believe Africans have lower IQs, that will result in an increase in prejudice.
Actually, I bet some people are not happy saying that there are correlations there. This is one of those notions you might want to double check.
So what you're saying is that it's ethically wrong to use Bayesian reasoning.
Is it inconceivable that this could ever be the case?
It is dangerous to be half a rationalist. This applies to groups as well as individuals. No matter how good your process for arriving at beliefs, it is indeed unethical to go around spreading those beliefs to people that will predictably misunderstand and misuse them.
Funny how the only people to make that argument tend to be people who don't want to believe the beliefs in question, but have out of ways to ignore the evidence.
On a less meta level: what kind of "misunderstand and misuse" do you think is going to "predictably" happen.
In the interest of clarity: I am not at all sure how to proceed in this particular case. History makes me wary of departing from the current Schelling point of assuming everybody is equal, but that's not my point.
I am saying that a course of action based on Bayesian reasoning has no special immunity to being ethically wrong, and it is those actual results that are worth worrying about, not merely the epistemology.
I, for one, do believe that the average African has lower IQ than the average European but don't go around telling that to the wrong people.
Underestimating how much the evidence race provides about an individual's IQ can be screened off by other evidence about the individual, due to the confirmation bias and similar.
It is almost always bad Bayes, or any other kind of reasoning, to make judgements about individuals based on group characeristics, since there is almost always information about them as individuals available which is almost always more reliable.
Group level information is still useful for shrinkage of estimates and correcting for the always-present unreliability in individual estimates; see for example the long conversation between me and Vaniver on LW somewhere where we work through how you would shrink males and females' SAT scores based on the College Board's published reliability numbers.
And E(X's deserved SAT score|X's measured SAT score; X is male) - E(X's deserved SAT score|X's measured SAT score; X is female) was, like, four points? I still think people's System 1 are likely to overestimate this difference if they know about the correlation more than underestimate it if they don't.
A 4 point adjustment (or more) across all candidates based solely on 1 binary variable (gender) and a trivial centuries-old bit of statistical reasoning seems like a fairly impressive output, and likely to make a difference on the margin for thousands of applications out of the millions sent each year.
And your evidence for this is...?
For applicants scoring 800 on a hypothetical normally distributed math SAT, yep. For normally distributed tests, shrinkage is linear based on the difference between the group mean and the measured mean, and so it's smaller for less extreme scores.
(For some reason, I'm having difficulty finding the link to the actual conversation; I think Google search is not going into deep comment threads, and the search function is based off the site, rather than just a database of my comments. Anyone remember helpful keywords further upthread to get a link to the actual conversation?)
Saying "we shouldn't explicitly calculate something because some people might implicitly calculate that thing incorrectly" sounds to me like going in the exact wrong direction.
Here is Wei Dai's tool for searching LW comments.
If you intend to use an African prejudgment heuristic like 1 (below) rather than reacting as if you've done an equation that takes into account other relevant data like 2 (below), then I think your probability equation needs an upgrade.
1) African prejudgment heuristic: "The IQ test(s) said African's IQs are lower than those of whites, therefore this specific African individual is likely to be relatively stupid compared to my white friends."
2) Reasoning that Takes Relevant Data Into Account: "The IQ test(s) said African's IQs are lower than those of whites. However, there are known flaws with IQ tests such as cultural bias, so that figure might be wrong. Most published research findings are false (PLOS Medicine), so I should apply healthy skepticism to all the research I read. This is not likely to be an accurate piece of data to use as a Bayesian prior. Once I've decided on a prior to use, I should then adjust for other relevant data (things I know about the specific individual).
Then, if one wants to behave rationally after one has decided what to believe, I think one must continue by thinking something like this:
"Considering things like...
A. ...the fact my prior is likely to be inaccurate (there isn't an accurate one for this subject as far as I'm aware)...
B. ...the fact that even if the IQ study is correct and the IQ test it used was accurate, there's a decent chance (25%) that this specific individual has an IQ above the African average - meaning I need to avoid the logical fallacy called hasty generalization...
C. ...the risk of lost utility via damaging this individual's reputation, emotional health or opportunities for success by pre-judging them...
D. ...the risk that this makes for bad social signaling and witnesses may retaliate against me with one or more forms of social rejection if I pre-emptively treat an African like an idiot...
...do I really want to treat this person as if they are less intelligent?"
I think you may have reacted to my "I hope it is false." statement or my "it's ethically wrong to prejudge individual Africans" statement - but that shouldn't matter to your probability calculation. What should matter is to get an accurate idea of reality. Along with saying other things, I also provided other factors which are relevant, as credible sources can confirm. If one wants to be a good Bayesian probabilist, after one specifies some prior probability, one must then update it in the light of new, relevant data. [1] This situation where you focused on one part of my comment and ignored the rest reminds me of those math problems where there's an irrelevant statement thrown in just to distract you. I of course did not intend to distract you, but since you seem to think that Bayesian reasoning in this case means ignoring all the other data I presented, it appears that you have skipped the parts of the process where you ensure an accurate prior and update your prior with new, relevant data.
Life is really, really complicated. I doubt it's ever wise to just grab a prior and run with it and I certainly hope that you do not reason this way.
All of that looks like rationalization of a pre-determined belief.
No it doesn't. The conclusion supported is far too close to the 'middle ground' on the issue to readily pattern match to rationalization and seems to be a description of considered reasoning from plausibly held premises. The 'rationalisation' and 'pre-determined belief' charges could be credibly made in response to many of the comments in this thread but doesn't apply to the grandparent.
NOTE: I don't entirely agree with with either Epiphany's position or Eugine's position. In particular Epiphany seems a little too disillusioned with research while Eugine has somewhat too much passion on the race/IQ political correctness subject to keep his claims balanced enough that I could support them despite agreeing that there are almost certainly IQ differences between groups selected by just about any significant feature---not that this seems like an especially useful thing to place emphasis on. I seem to recall some credible claims about higher average mathematical intelligence in Ashkenazi Jews for example.
Regardless of whether I agree with the position being argued with, the parent is making what seems to me to be a false accusation and one of a kind that derails the flow of discourse.
Respectfully disagree, though we may be focusing on different parts. It worries me that your analysis seems to focus on the conclusion drawn rather than the procedures followed.
Consider this bit of the great-grandparent:
This looks like pure rationalization to me, with many inaccuracies and irrelevancies, all of which support the intended conclusion. (An unbiased sloppy thinker should be expected to make mistakes in both directions simultaneously; when the mistakes all point one way it suggests bias.) The most egregious irrelevance is the attempt to discredit one of the most replicated findings in social science with a study that showed that prominently promoted recent research often fails to replicate. The last sentence is bizarre by its addition- would someone using race as Bayesian evidence not update on other information? (The later reference on Bayesian updating is similarly bizarre.)
The rest of the great-grandparent discusses how, even if we had an estimate, we should be careful how we use that estimate. Of course--who would argue against using estimates carefully?--but irrelevant to the question of whether or not it is ethical to use Bayesian reasoning.
This reads like a classic case of motivated cognition. You don't want to believe the conclusion; therefore, you selectively look for potential flaws then declare that there's still a chance. The reason I believe the connection between race and intelligence is not just because of the tests but because more or less every relevant aspect of reality (e.g., the statistic on race and crime, the nearly complete lack of blacks in intelligence intensive fields, e.g., math, programing, the state of majority black countries) looks the way one would expect it to look if the connection existed.
Who is claiming otherwise?
Yes there is. You just don't want to believe it exists.
Actually the chance of this particular black being above the African average is 50% (more if I condition on the fact that he is in the USA). The probability that he is above the white average is significantly less. The probability that he is above some high cutoff is can be even lower.
This is a general argument against using evidence of any kind.
This is potentially a problem, although here the problem is arguably with the witnesses behaving irrationally and/or participating in out of control signaling arms races than with the strategy itself.
Did you stop to make distinction between me being influenced by motivated cognition and alternate explanations like:
Me seeing significant flaws in data that would otherwise support your conclusion. Part of this may be that I've spent a significant amount of time reading about IQ and giftedness and I have learned that there are a lot of pitfalls to doing IQ related research.
Me simply being unaware of relevant data. (This might be the case in the event that the people who supplied my data were influenced by motivated cognition or confirmation bias.)
You seeing motivated cognition in my words because of being influenced by motivated cognition yourself?
There is an alternate explanation for those which does not have the same issues that IQ tests and studies have: The effects of slavery and prejudice. We are certain that slavery and prejudice has influenced them, and that it has existed for a long time. To know this, one must only look at the KKK or investigate the history of black enslavement. Imagine a third world country. Imagine that an equal proportion of those inhabitants are removed and used as slaves. Imagine an equal proportion of them dying. Imagine that they're freed, but all of them - not some but all - are freed into a situation of extreme poverty where they don't even own a home or have the ability to read. Many still aren't being taught to read. Consider also that even though there have been advances in medicine, poverty means you can't afford health insurance or medical treatments. Don't think that disability and chronic illness are uncommon - they're not. Not even in America. They're probably especially common for the poor. Don't think that severe worker abuse ended with slavery, either - do some research on sweatshops in America sometime. Now take into account the effects of stress, and the human element - how those effects can compound into things like mental illnesses and drug addictions. Would you predict that the majority of these people who started out with literally nothing and without even the education to read would manage to avoid pitfalls like disability, mental illness, drug addiction and sweatshops and carve an opportunity to excel out of poverty and ignorance over the course of 150 years? I would not expect that. I would expect most of them to have fared poorly.
I don't see a good way to tell the difference between a low IQ score due to actually being less intelligent versus a low IQ score due to nurture-related reasons such as the following:
If you want to attribute the IQ scores to race, not poverty or circumstances, then there needs to be a good way to distinguish between nurture and nature as a cause for low IQ scores. Do you have one?
If it's true I want to believe it. However, it's hard to believe it exists without a citation. Do you have one?
I respect you more for being able to say something that supports my view better than it does yours. +1 karma for that. I still think the number is 25%, however I do not view this as a key point in our disagreement, so I will leave it at that.
You appear to have taken that statement as an argument regarding what to believe. It was not. I deliberately put that part after the section where I was discussing deciding what to believe, and put it under "if one wants to behave rationally".
In Africa? It so happens that the world is much bigger than the USA and the people in sub-Saharan Africa test for IQ pretty much the same as African-Americans.
Sure, you can control for wealth/economic status. Or you can go and test poor peasants in China and poor peasants in Africa. You seem to think that this is a white-vs-black US problem. It's not. The highest-average-IQ large group of people is East Asians, like Han Chinese -- not Caucasian whites.
I am curious -- how do you figure out that in a distribution close to normal only 25% are higher than the mean?
Actually much of sub-Saharan Africa has average IQ around 70, whereas African-Americans average around 85.
If your point is that it's not clear to what extent the difference in intelligence is due to nature or nurture, I agree but would like to point out that for many applications it doesn't matter.
"X have a lower IQ on average."
You can choose "People of African descent" or you can choose "People from poor backgrounds" or "People with serious health conditions" or "People with drug addictions" or any number of other things.
When attempting to determine how best to help a school in a black ghetto that is failing, and you're choosing between spending money on remedial courses or on a school nutrition program, you will most certainly benefit from having this knowledge.
Conversely, I can't think of any applications for which tying IQ to race is useful. Would you name three examples?
Also, I'm still interested in seeing the source that you believe is an accurate prior regarding race and IQ. Do you happen to have that information available?
As the saying goes, "Life is an IQ test." The predictive ability of IQ on income (and most other statistics of interest) is very similar for each race, which suggests that differences in measured IQ scores map onto differences in life outcomes. To the extent that a medical condition makes someone test poorly, it generally also makes them live poorly. (There are a handful of prominent exceptions to this- like dyslexia- which don't significantly impact the main point.)
Now, where those IQ differences come from in the first place is an interesting question. Many people have looked at it, and the consensus answer for individual IQ differences is "somewhere between 50% and 80% of it is genetic," and the extrapolation from that to group IQ differences is somewhat controversial but seems straightforward to me. A perhaps more interesting question is "what knobs do we have to adjust those IQ differences?"
Here's Jason Richwine explaining that all serious scientists have agreed on the basics of IQ for decades, and the media is completely mistaken on the state of reality and scientific consensus.
It seems pretty relevant to me, because it looks like basic statistical innumeracy on your part, unless you think the IQ distribution of African Americans is tremendously skewed such that the mean intelligence is the 75th percentile of intelligence, rather than the 50th percentile like it would be in a symmetric distribution. (Or you think that the African average is higher than the African American average, which is very much not the case.)
As a stand-alone statement, I would probably leave this alone. But as a response to "What about nurture", the first thing that comes to mind is:
Has Vaniver adequately corrected for the just world fallacy?
Ok, that's interesting, but it does nothing to rule out nurture factors that would impact both IQ and income.
I agree that IQ is mostly genetic and that IQ does seem to correlate with a lot of factors. I'm not saying IQ does not exist. What I am saying is that, specifically when it comes to black people, there are other factors that are definitely influencing performance and IQ scores. Therefore I reject claims about IQ and race that haven't controlled for known factors.
Actually, when I read that section (it starts with "What scholars"), I parsed it like this:
Jason explicitly says that there's a scientific consensus on many issues that seem controversial to journalists.
Jason states that virtually all psychologists (not scientists) believe there is a general mental ability factor (That he's not saying is specifically connected to race).
Then, without qualifying these statements with anything along the lines of "most x believe", he states: "In terms of group differences, people of northeast Asian descent have higher average IQ scores than people of European lineage, who in turn have higher average scores than people of sub-Saharan African descent."
I will not assume that this sequence of claims means that the group differences statement is also something scientists have a consensus about. If I did, that would be a non-sequitur.
Also, below that, he writes:
"It is possible that genetic factors could influence IQ differences among ethnic groups, but many scientists are withholding judgment until DNA studies are able to link specific gene combinations with IQ."
This is where I stop reading the article because it is clear to me that it does not say "there's a scientific consensus that there's a link between race and IQ". If you have a credible source for that claim, I'll be curious about it. No more Politico articles please.
It might or might not have been an error. In any case, I'm not going to go digging for that right now because I still think knowing the percentage is irrelevant to the current point. Whether the figure is 50% or 25%, it is still true that a significant proportion of people will have an IQ above average and therefore it would be hasty generalization to assume that a person of a certain group was an idiot. That is one way in which the exact number is irrelevant. However, that point about hasty generalization is much more irrelevant at this particular moment because we haven't even decided on a prior, let alone have we got a decent posterior - so the step where we have a concern about making a hasty generalization based on our probabilities should be in this disagreement's future. If it becomes relevant, I will dig around, but not right now.
That's a saying? Are there also sayings "Life is a test of height.", "Life is a test of immune system efficiency" and "Life is a test of facial symmetry"? We may as well round out the set. Anything of comparable test significance that I missed? Oh! "Life is a test of breast perkiness" and "Life is a test of capacity for situation-appropriate violence."
(I actually agree with the point of the rest of the paragraph.)