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Flynn’s IQ (bryanappleyard.com)
197 points by tortilla on Aug 31, 2012 | hide | past | web | favorite | 135 comments

Wait, people take IQ tests seriously? Really?

I was tested twice when I was in second grade, the first time by a psychologist in a class setting and the second time one-on-one to verify the first. I tested quite high, but even then I knew I wasn't noticeably smarter than others; I just test particularly well.

Frankly, it cracks me up when someone refers to their IQ seriously or boasts about being in Mensa. Other than testing for mid-to-high level mental retardation, subjectively, IQ tests seem to be terrible at measuring actual brilliance.

I don't know about "IQ tests seem to be terrible at measuring actual brilliance." - Some of the components of IQ tests are fantastically accurate. I can't read maps, I can't put a monitor back in it's box. And I score very poorly on the pattern assessment components of IQ tests. I guess you might say I'm "mid-to-high level mentally retarded on pattern assessment."

Likewise, I have a friend who is world class _stellar_ at putting Monitors back in complicated styrofoam packing and into boxes (Seriously - his ability in this task is amazing) - and he tests off the chart on the pattern recognition component of IQ tests.

So - I can, based on the admittedly small anecdotal sample of n=2, suggest that there is strong predictive power of at least some elements of the IQ tests.

I think the main point is that IQ measures some sort of current fluid intelligence. It doesn't measure other types of intelligence, and most importantly it doesn't measure potential. So the blanket concept of it defining someone's common-understanding-of-"intelligence" is flawed to the extent of it being a pointless or harmful measure in many of cases.

What I'm arguing is the opposite - that the IQ test actually is precisely a measure of potential in various abstract areas. Whether you do anything with that potential, or how you develop it (as, in the case of my friend, who is a savant in putting Monitors back into styrofoam boxes) - is a function of resources, opportunity, and interest.

Flynn goes further, and suggests that the society and culture that you grow up in, also enhance your ability to execute on IQ tests. The genetic potential (obviously?) hasn't changed, but the environment has shifted such that our "actuated" IQ has increased as we practice more often in abstract tests.

>> that the IQ test actually is precisely a measure of potential in various abstract areas.

I'm trying to understand this. Here's my understanding: That it is possible to take an IQ test and have score x, then perform activities y, retake the IQ test and have the score x+15. How exactly did the initial test measure the potential for that increase? That your potential is x (+-)15 (or 25 or whatever the number is)?

IQ measures your potential to perform and learn in various areas. Per wikipedia, one of the standard suite of tests includes, "Comprehension-Knowledge, Long-Term Retrieval, Visual-Spatial Thinking, Auditory Processing, Fluid Reasoning, Processing Speed, Short-Term Memory and Quantitative Knowledge and Reading-Writing Ability"

The argument that James Flynn makes, is that your potential can increase, through your environment.

That is - your IQ isn't simply a function of your genetics, but also of what you are exposed to.

To put it in concrete terms - someone who worked every day, from dawn to dusk, in very manual labor - let's say cutting wood, chopping it up, and stacking it, will develop their potential for abstract thinking very differently than if they had instead gone and gotten their PHD in some abstract field like Logic.

Same person, same genetics - very different IQ.

What you are referring to, is closer to the "Potential for Potential" - I don't know if there is any way, or anyone who measures something like that. But I think that everyone will agree, that IQ is _not_ a measure of your "Potential for Potential" - simply a measurement of your potential - and that is malleable.

I think many people believe that IQ is your potential for potential, and indeed the potential for potential of your descendants and your "race". Thats what people generally mean when they say Group X has a high/low IQ. I think this might be referred to as the strong IQ hypothesis.

> What you are referring to, is closer to the "Potential for Potential" - I don't know if there is any way, or anyone who measures something like that.

Your parent poster is definitely referring to this concept. (S)he is referring to that concept explicitly because it is so ill-definable and unmeasurable.

It's pointless to judge an accomplished person, like a businessman or scientist, with an IQ test, because that misses the point. It's just a very quick (15 minute) way to categorize people efficiently.

So, if the army wants to determine who should be an officer candidate, or an NCO, or a radar operator, or a potato peeler, when they have 3 million men to process, it's incredibly efficient. If you are interviewing 10 candidates for a management position, an IQ test would make no sense.

Why does it have to be about brilliance. The US armed forces is one of the bigger users of IQ tests and has plenty of data showing higher IQ scores leads to better performance.

I think it would be fascinating to view the outliers (low IQ when measured=high performance) and investigate the reasons.

(My hypothesis:) Naturally what I would expect would be found is that IQ is just one measure that sometimes correlates in certain types of people, and that it completely fails and miscalculates actual intelligence and mis-predicts future performance in other types of people. And that it fails in a statistically significant number of cases. And that due to the behavior confirmation effect (self-fulfilling prophecy) it ends up true in more cases than it could.

Meaning IQ is an OK measure in many cases, but very flawed. I'm curious what will eventually take it's place as more useful.

It is my understanding the DoD uses IQ test only for initial entry into the various services. I believe the threshold is 105 (although some military guys have said that at the peak of the Iraq & Afghan campaigns recruiters would let a few sub 105s in, quotas & bonuses.) I would be interested in a link to those studies (if you have them available.)

> Frankly, it cracks me up when someone refers to their IQ seriously or boasts about being in Mensa. Other than testing for mid-to-high level mental retardation, subjectively, IQ tests seem to be terrible at measuring actual brilliance.

Frankly, it cracks me up that you're so confident in your opinion when you argue past a strawman and demonstrate incredible ignorance about IQ tests.

> I tested quite high, but even then I knew I wasn't noticeably smarter than others

Now we're onto something.

Am I the only one who refuses to take an IQ test? I hate being tested - especially with a time limit, I rarely play games (chess and logic puzzles being the exception) but above all I don't understand how anyone could not have an emotional response being told 'your IQ is x'.

My mom is a children's psychologist who used to administer certain tests. I know I was tested as a child, due to requirements of the school I went to, but my mom didn't look at the results and never showed them to me.

She was worried that it could affect the way she treated me and my success (or lack of success) in school if she had some expectations based on a single number.

Are you saying it's rational to avoid things that might cause an emotional response? Should I not have attempted Stripe's CTF challenge since, as a web developer, it would have been demoralizing to fail?

The IQ test is, to many people, an evaluation of themselves and their capabilities. It may even be received as an assessment of one's limits.

If you think that the Stripe CTF challenge has the potential to evaluate and define you as an individual, then perhaps you should either think twice about it, or work really hard. For most entrants, and I guess probably you too, it's a harmless and fun challenge with very few implications for your core identity.

So the real problem is perception of the test, not the fact that one might get emotional...

That's not the same thing: you're not given a time-limited test that has specific answers. A challenge means solving problems in creative ways: that kind of test is fascinating and in no way demoralizing unless you haven't learnt that even failure can be useful in it itself for the fact of trying.

Stripe CTF had a time limit and required very specific solutions. Figuring out the answers on an IQ test often involves creative problem solving. I don't see a difference except in an individual's preconceived notions about the significance of the test itself.

Yes, but the Stripe CTF isn't going to compare you to the entire body of humanity: just to the already-brilliant people who want to take a crack at it. I didn't know about the challenge, but I'd consider if I failed at it, that I don't have sufficient knowledge in a certain technology area, not that my ability to abstract and reason is measured to a global degree.

No, I refuse to take an IQ test as well. Not because I would feel afraid to have an IQ score associated with me. Rather because I think that the concept of an IQ score is rather silly and I question our overall ability to measure it via a standardized test.

First, Intelligence (as probably this article says) is an ever evolving concept and its multidimensional. Accurately measuring it seems probably impossible, the least really hard. The way we attempt to measure it, is via standardized tests - but those don't really prove much because instead of really measuring what they should measure, they usually end up measuring "test-taking" abilities.

Just think about Einstein and Leonardo da Vinci for that matter. Einsten did terrible in school and would have probably done terrible on an IQ tests. Leonardo da Vinci (arguably the greatest genius of all history) was rather slow in problem solving, but increadibly effective. He would have probably done terrible on a timed standardized test.

Please don't spread legends. Einstein excelled in school, and his grades were fine (his only weak subject was French, which he apparently had little interest in). See http://www.albert-einstein.org/article_handicap.html .

I may be wrong, but I'm reasonably confident that Einstein did not do well in elementary school and while he was in school in Italy. He also failed his University admission exam: http://www.pbs.org/wgbh/aso/databank/entries/bpeins.html

Yes, you are wrong. Einstein did very well in elementary school, and was accepted to a competitive gymnasium at age 9. He also did very well at the gymnasium, although he didn't like the rigid structure. He left school at 15 and applied to university with special permission. He was not admitted due to mediocre grades in French and Latin; his exam grades in Physics, Mathematics, and Chemistry were excellent. He finished another year at school and passed the entrance exams with excellent grades. Hardly an underachiever, although it's true that you couldn't tell the later greatness from this.

In fact, he had finished Euclid's Elements textbook at age 11 and had taught himself calculus by 16 (not an unusual accomplishment these days, I admit -- I also taught myself calculus at 15. I am no Einstein.)

In no way was Einstein deficient -- he would at least be described as advanced, just maybe not as a prodigy.

No, you're the one that's wrong. Einstein did poorly in elementary school, being classified as mentally retarded. He indeed fast-tracked to gymnasium and university after one of his teachers observed his talent at math.

This doesn't mean he was stupid. Go and read "The Einstein Syndrome" [1], it's a fascinating read.

[1] http://www.amazon.com/The-Einstein-Syndrome-Bright-Children/...

Your information is completely ridiculous, and doesn't become less so because it has appeared in some books. It has been debunked not by some random guy on the internet, but by the Albert Einstein Archives at Hebrew University, to which he willed his documents - as I cited earlier.

Einstein started in the second grade of elementary school at age 6 1/2, was one of the top students in his class, and was admitted to a competitive gymnasium at 9 1/2. He studied not just "math", but Latin, Greek, art, music (he was a very talented violinist who could have played with any number of orchestras), literature, history, philosophy, and theology. He did very well in all of these, was not "fast tracked" to anywhere, and tried, on his own, to enter university more than 1 year early. This failed, largely because French was not a strong subject for him. He studied it in Munich, where it was a lot less important than in multi-lingual Switzerland. After half a year of schooling in Switzerland, he passed the university entrance exams with flying colors, both in sciences and humanities. He was not an incredible child prodigy, but he was doing fine, and nobody ever thought he was mentally retarded. Enough.

That page doesn't say anything about university admission exam.

I was tested once, in high school, for the so-called 'gifted' program. We were not supposed to be shown our scores, but I did see mine. No emotional response. It told me what I was already knew... that I was good at taking standardized tests. Real problem solving skills came later, and were largely a product of working with people who were experienced, patient, and generous.

It's a sign of a high EQ to have a neutral response to being told 'your IQ is x'. It's actually just another part of the battery of psychological tests.

I've never heard anyone claim to have an IQ less than 125.

That could easily be true without people lying (though probably not). If you take a test and score a 99, you aren't exactly about to run around saying "Hey everyone, I'm very slightly below average according to an IQ test!"

There is a lot of selection bias there. 9 out of 10 people I see day-to-day make more than twice the per-capita median income. That isn't evidence that the median income is incorrectly computed.

I agree that it's selection bias.

The kind of people who go around talking / bragging about their IQs are likely to overlap with that set of people that score well on formal cognitive tests, IQ or otherwise. (See, the entire membership of "Mensa", for example.)

(And if a person who was very into tests and intelligence also scored 95, you'd probably not hear a peep out of them - it would misalign with their self image.)

Finally, the typical person scoring 80-85 in IQ is not likely to be the kind of person who enjoys taking such tests, or considers their IQ or their intellectual ability as an important aspect of their personal identity.

I got a bit of confirmation of that while taking an IQ test at a Mensa meeting. The proctor mentioned that generally something like 2/3 of the people who took the test there scored well enough to get in.

Did you have an emotional response when you learned that you could only hold "7, plus or minus 2" things in your short-term working memory? Or when you found out what your adult height was going to be for the rest of your life?

The 7 plus or minus two thing is universal. Adult height non-universal, but less emotionally sensitive. Even so, it's easy to be sensitive about one's height.

IQ is a comparison between you and everyone else, on a topic which is close to the core of our being, especially for the kind of people on this forum.

I find height way more emotionally charged than IQ.

I guess I shouldn't have assumed everyone thought like me. :) Is it more sensitive than intelligence in general, or just IQ? Would you react more strongly to being called "shrimp" than "stupid"?

I don't care about names. But looking down instead of up makes quite a big difference.

I don't really believe in IQ as anything more than a statistical artefact in the first place. But of course, different people are going to perform differently on different tasks.

>Did you have an emotional response when you learned that you could only hold "7, plus or minus 2" things in your short-term working memory?

Well, no - because I could use tools to extend that. And it's not about insecurity, as I'm quite comfortable with myself and my brain. I just don't see it as being a valuable reference. However, I know if I had a number I'd start comparison-shopping and I might feel either elated (if high) or depressed (if low). Is anyone here, if you have had an IQ test, honestly prepared to say that you didn't or wouldn't be curious about what that meant and that it wouldn't affect how you viewed yourself?

I just don't need to know. I guess that for me, as long as there isn't a 'goal' or a 'fence', the sky's the limit.

You can extend your effective IQ using tools as well. I bet your IQ as tested while you have access to an internet-connected computer would be way higher than your IQ as tested on a closed-book test.

I doubt it, unless you could find a cheat sheet for the test you are taking. It's not like the test is asking about information, facts or calculations; what would you type in to Google to answer a question like this? http://upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Rav...

It's not like purely visual questions are the only ones you'll encounter. And the Internet has plenty to offer for your question too, you just have to involve some actual people.

IQ tests are timed. It's usually not worth it to look up any answer, because the time it takes you to do this would make you skip so many other questions that your score would take a massive hit.

It's the same thing with the SAT (before they added the writing sections). It usually paid to just guess & move on if you faced a difficult question, because the time spent thinking about it would cost you so many other answers that you were better off just eating the penalty for getting it wrong. People who could actually complete the (old) SATs were at a strong advantage, as one of the most common failure modes was simply not being able to answer all the questions.

I have a very emotional response each morning, when, depending on the quality/duration of sleep I had the night before, and whether I had a late night snack, I'm able to memorize the 10 digit (Yes, 10) passcode for whatever conference call I have to dial into. I know it's going to be a good day when (about 10-20% of the time) - I can nail it in one try. Not so much when it takes me a round trip to the calendar entry. Particularly when the conference service times out.

Does anyone have a good source or summary on this "7, plus or minus 2" thing? I teach the LSAT, and have noticed it empirically when students try to solve the Logic Games section.

I've love to know more about the research backing this up. I googled, of course, but I'm sure there must be a good discussion of this that I've missed.

The phrase is from an interesting paper from the '50s about some limitations of human cognition. https://en.wikipedia.org/wiki/The_Magical_Number_Seven,_Plus...


I don't refuse to take them but midway through I always start thinking about the philosophical implications Wittgenstein rule following paradox, computational learning theory and solvable games.

I also wonder if I would have a higher IQ (or would that be an IQ that appears higher?) were I not to think those thoughts (and would I be stupid for thinking them in that case?)

And what if I'm just distracting myself thinking about irrelevant philosophical problems because I'm too stupid for the test?

> I don't understand how anyone could not have an emotional response being told 'your IQ is x'.

This is a wild guess: You're probably ~young, with high aspirations for yourself, you don't think people should ever be prejudged. You have great promise and show all the signs of competence, but you haven't actually achieved anything particularly noteworthy, yet.

I base this hypothesis on the theory that once you achieve certain things, and you have confidence in yourself, you won't give two shits about what some IQ test says. In fact, if it scores low, if you are genuinely competent, you would think "wow, now that's an interesting development, let's investigate" rather then feeling that you've been somehow slighted.

I also refuse. I worry that if I had a high score I'd be a douche about or if I had a low score I'd resign myself to lower goals.

So the vast majority of people misunderstand intelligence, at least as measured by IQ tests, as being a limiting factor for performance and potential, while it is actually just a measurement of current abilities.

> the penultimate chapter is a list of 14 examples in which science has failed because of social blindness.

This carries through more broadly and generally to the application of many incorrect fundamental assumptions to the design of our institutions, which consistently fail because of the resulting flawed structures.

It is a limiting factor for many tasks, even such "simple" tasks as basic algebra and calculus. A lot of people fail at math simply because they do not have enough brainpower.

No, they fail at math because they have never learned how to use their brainpower effectively. The difference between geniuses and everyone else, from my experiences, are not any fundamental difference in their brain wiring, but that they learned how to better focus what brainpower they do have,

Its like the difference between a guy who gives 120% every day but his work, taken individually, is mediocre vs a guy who gives his 1% but his 1% is the Nobel prize winning work of his field... the guy who gives his 120% day in and day out is a smarter man.

Ironically, an IQ test will not say much about either of them. The 120% guy might score lower than the 1% man by 10 or 15 points, but the 120% guy, if he were, say, a researcher or inventor, would be spending day in and day out finding thousands of ways that don't work just so he can find one that does. The 120% man learned how to focus the skills he does have and learned how to apply them well; of the two, I'd hire him over the 1% man, Nobel or not.

The few super geniuses that history remembers (such as Tesla) had both: 120% work ethic combined with a brilliant mind. These people are rare, but every single person no matter their racial or religious background has the ability to become that kind of person to.... they just never learn how to.

"but every single person no matter their racial or religious background has the ability to become that kind of person to..."

Seriously? I don't know, but even if i had a 120% work ethic, i consider that i would never reach the level of genius of someone like Tesla, he is simply a genetic freak. Also, almost all the traits of humans seem to be unevenly undistributed in the population, not everyone has the capability to be a top athlete or top dancer, or top X. Why intelligence could be the exception?, when even common sense and observation tells us that some people are more intelligent than others.

Chess is an interesting proxy for intelligence. I've seen homeless people with no real training other then playing games become relatively strong players. And then there are prodigies. Most decent players realize they will never be prodigies. But then you look at the Polgar sisters, well I'll just quote wikipedia for Laszlo Polgar:

He is interested in the proper method of rearing children, believing that "geniuses are made, not born". Before he had any children, he wrote a book entitled Bring Up Genius!, and sought a wife to help him carry out his experiment. He found one in Klara, a schoolteacher, who lived in a Hungarian-speaking enclave in Ukraine. He married her in the USSR and brought her to Hungary. He home-schooled their three daughters, primarily in chess, and all three went on to become strong players.


"Strong players" is an understatement for Judit's accomplishments which are well known.

> common sense and observation tells us that some people are more intelligent than others.

Yes, true, but the present discussion concerns why that is so. It was traditionally held that IQ was inherited and immutable, but this was before studies that show creation of new brain cells in animals placed in stimulating environments. And the brain's ability to repair itself after injury is only beginning to be appreciated.

So it seems that IQ is not immutable, and "some people are smarter than others" can be placed alongside "some people run faster than others" as an example of something that is to some extent under our control.

I'm leaning against (but not convinced against) "intelligence genes" existing, at least to the point where some people have them and some don't, because evolution would likely have spread them to everyone.

But the science is much better for behaviors and temperaments being heritable. Some people are more comfortable sitting around only reading; some people are more likely to be comfortable fighting with abstract ideas; some people are more likely to be stubborn when they don't understand something and go at it until they figure it out. These things will affect what we measure as your IQ. My suspicion is that this is the source of the data for genetic differences in intelligence.

There's pretty robust evidence for intelligence (at least as measured by IQ) being heritable. There've been a bunch of identical-twin studies showing heritability factors as high as 0.8, which is roughly as heritable as height and among the highest of personality traits:


As for why these intelligence genes wouldn't spread throughout the population: it could be because they have other effects with a negative survival/reproductive value as well. Intelligence is often inversely correlated with confidence, for example, since people's expectations of themselves rise faster than their abilities. Confidence is heavily correlated with social skill and the ability to attract a mate, so highly intelligent people often face severe deficits in the mating game (I'm sure we all know someone who is brilliant but completely socially inept, and many of us have been that person).

Also, remember that the ancestral environment that humans evolved in significantly less favorable to intelligence than the modern one. 15,000 years ago, intelligence might be nice, but the ability to outrun a lion or take down a buffalo was far more important. It's only within the last 3-5 generations that intelligence has become essential to surviving in modern society (that's the whole point of Flynn's thesis), and evolution doesn't work so well on a timescale of 3-5 generations.

I'm leaning against (but not convinced against) "intelligence genes" existing, at least to the point where some people have them and some don't, because evolution would likely have spread them to everyone.

Why? What survivability/reproduction benefits does intelligence provide beyond a certain level, particularly in pre-modern society? If you were the daughter of serfs a thousand years ago, what good would a 150 IQ do you? Especially if there's some tradeoff involved, such as a correspondingly lower ability to socialize with your peers.

Especially if there's some tradeoff involved, such as a correspondingly lower ability to socialize with your peers

If there's any reason for an "intelligence gene" not being completely wide-spread, it would be this. Intelligence would have to have some very significant drawbacks. Some people have theorized that autism is when you get "overloaded" on those intelligence genes. It strikes me as unlikely this would really provide significant pushback against the intelligence genes completely dominating the gene pool, but I agree it's possible.

But why? Even if there's no tradeoff, what advantage would Albert Einstein have had over an average intelligence competitor for mates had he lived even a mere 200 years ago? Slim, I'd think. And who's to say he would have used that narrow advantage to win a mate of above average intelligence, vs. some other desirable characteristic?

Exceptional intelligence as a strong determinant of economic and social success (and thus presumably reproductive success) seems to be a relatively recent phenomenon in the human species.

Also, we need to take a larger view of what "intelligence" is. Take the longer view of human history, and we all are probably geniuses. Those intelligence genes have indeed spread across the gene pool. It's just new ones (or new combinations of existing genes) are now showing themselves and need time to prove their fitness.

The downvotes are unfortunate, because you're absolutely right. Intelligence has an associated cost. Natural selection will only spread "intelligence genes" if the benefit outweighs the cost. In pre-modern societies, this was likely not the case. "Social intelligence" was likely much more useful than abstract reasoning ability.

Even today, the Einsteins and Teslas don't do better in the mating game than the Brad Pitts and Kobe Bryants (likely much worse).

Edit: it would be interesting if HN handles were attached to downvotes. People would likely think twice before knee-jerk downvoting if they couldn't do it anonymously.

>because evolution would likely have spread them to everyone.

This is just your bias in what you think is more beneficial informing your belief that more intelligence = better survival. If this is the case, why aren't all apes just as intelligent as us? Has no ape simply ever had the luck to have a mutation that improved the carrier's intelligence? This is implausible. The answer is that one's environment determines what is selected for, and it is not the case that more intelligence is necessarily more fit for survival. Not even in modern times.

My impression is that IQ seems to be a measurement of a person's capacity to think abstractly, which is something you learn through the world around you. Perhaps those who fail at math have simply never experienced anything that requires abstract thought. Therefore, it seems like there is a skill that even basic arithmetic is dependent upon, basic abstractions. I can see how an otherwise able person would be hopeless at math if they never learned abstract thought.

"Perhaps those who fail at math have simply never experienced anything that requires abstract thought."

I disagree. Most math classes are structured as far away from the abstract as possible. Math classes, at least in the US high schools, are simply students sitting down and crunching numbers on paper with 40 other people around you. How is that abstract thought? I'm not saying math isn't useful in the abstract, I'm saying the way we measure people's math abilities is too focused.

Crunching numbers is most definitely abstract. What is a number? Why does it matter? What does it represent? What is zero? Why is zero important? Think about how long it took for humans to actually start doing math. And then think about how difficult it used to be for people to grasp negative numbers. Sure, schools teach things with M&Ms and counting other concrete things, but you still have to think abstractly to apply the same concepts to other concrete things.

I assure you, passing Oregon high school's math classes without abstract thought is VERY easy.

If you spend lots of brainpower on basic algebra and calculus, you are doing it wrong. Learn the tricks (i.e. theory), and it'll be so easy that even a computer can do it.

The Flynn effect tends to be used to support the feeling that intelligence isn't something you're born with.

People who think that intelligence is innate will refer to the "g factor". http://en.wikipedia.org/wiki/G_factor_%28psychometrics%29

The racist (technically speaking) and controversial Jean Rushton believes that "gains in IQ over time (the Lynn-Flynn effect) are unrelated to g".

What's really going on with discussions like this is that humanity seems to have come to the conclusion that "smarter is better". Intelligence almost certainly exists, but is quite difficult to quantify exactly, and is further complicated by the fact that people resent others who are "better" than them. Given that there is a genetic component to intelligence to a certain degree, race becomes a factor and leads to a line of inductive reasoning that makes people uncomfortable:

  1) Smarter is better
  2) Intelligence is genetic
  3) Race determines genetics
  4) One race is better than another
  5) Hitler was right (or other outrageous conclusion)
As far as I can tell when you see terms like "g factor", "Flynn effect", "multiple intelligences", "crystallized intelligence", "fluid intelligence", "cultural fair IQ tests", "The bell curve"... people are really secretly arguing about one race or sex being smarter than the other, or not.

The idea of a measurable "G factor" isn't incompatible with Flynn's work. He simply argues that the value of G is determined by social context and background. So to go straight for the hotbutton interpretation: arguments of the form "Blacks are less intelligent than whites due to genetic factors, as measured by IQ scores" is unsupportable simply because those same whites are smarter than their own grandparents (i.e. the same gene pool) were at the same age, and as measured by the same tests. That is, there is clear proof that non-genetic factors can cause that effect, so absent specific evidence arguments for "racial intelligence" must be dropped via Occam's razor.

Points 1-2 are valid, though intelligence is not entirely genetic.

Your points 3-5 are completely wrong. Genetics determines race, not the other way around. Points 4 and 5 are just meaningless "racist" phrases, not statements in a line of reasoning.

It may be semantics, but genetics certainly does not determine "race" alone. If it did, "african american" and "hispanic" wouldn't exist as "races". The idea of classifying people like that doesn't work genetically. First, people have been interbreeding like rabbits throughout history; there are no "pure" stocks anywhere. And more importantly, the amount of genetic variation between any two individuals from the same "race" is much higher than it is, statistically, between the aggregate genetic profiles of distinct "races".

Basically, "race" is a cultural distinction. It's a label we apply as a proxy for other stuff (usually cultural). Scientists (well, except anthropologists studying that cultural stuff) don't use it, and for good reason.

You might fight about what name it's given, but someone's ancestry is definitely measurable and quite usable by whatever normal scientific tests you would normally come up with.

Just off the top of my head, there are over 93000 references in PubMed to "ancestry." They vary whether they call it "race" or "ethnicity" or "region of ancestral origin" but plenty of adults are quite happy talking about it.

You're strawmaning. I didn't say ancestry had no meaning. I said it wasn't determined genetically, which is 100% true. There's no blood test for "black", and I encourage you to cite one if you're aware of it. If you have a big population, you can do things like look at frequencies of specific gene variants and come up with a guess at where that population came from. But for one person there's just no way to do it. So: can a person, in isolation, be part of a genetic "race"? No.

There's no blood test for "black", and I encourage you to cite one if you're aware of it.

Now who is strawmanning? (BTW, there is no blood test for autism, yet scientists are pretty darn sure it's mostly genetic.)

I'm sure you can come up with a definition of "Polynesian" such that genetic tests would be useless. That more shows that people can some up with useless definitions. However, someone else can could up with a definition of "Polynesian" that is useful: people whose ancestors inhabited Polynesia (say) 1000 years ago. And genetic tests for any individual in isolation would be very very very highly correlated with the actual answer of their ancestors coming from Polynesia. (There are, of course, people of mixed ancestry, but this doesn't mean that ancestral measures don't exist no more than hermaphrodites mean sex doesn't exist.) "Black" would need serious subdivision, but nothing that makes a person on the street drop their jaw and say "I never thought of 'Black' that way."

I suspect this is as far as constructive discussion has gone, so I'm going to stop here if that's okay.

Arrgh. I still think you're fundamentally missing my point. You can't treat "black" via subdivision. The problem is mixing (i.e. most "blacks" are "half white", etc...), not imprecision. Basically you can't treat "black" at all. The term will never be useful to scientific study. The fact that there exist some identifiable ancestral groups will never (!) tell you anything useful about a typical "black" woman in america.

The same is true of "polynesian" -- sure, they might have been isolated at one point but by now almost every "polynesian" you meet in Hawaii has a ton of white and japanese ancestry too (substitute appropriate mixing for Maori or Samoan and Fijian, etc...), so what use is it to talk about the potential IQ effects his great-great-grandparents might have had?

Yet the argument at hand (that, as far as I can tell, you are in support of) is that somehow the "race" of real people can, because it is "genetically determined", be correlated with something like IQ, which it just can't. It's far too polluted a data set.

You're falling into the fallacy of the excluded middle. Just because "black" doesn't tell you everything about a person doesn't mean it can't tell you something useful.

That typical (now there's an overgeneral term!) black woman will have a darker skin color than a typical white woman. She will be less susceptible to sunburn. She is more likely to suffer from certain genetic diseases like sickle cell anemia.

Now, none of these are absolute statements. They are all probabilities. That does not make them useless. If someone comes into the ER with severe pain in their extremities, it is very useful to know that they're black. They may or may not have sickle cell anemia - that can be determined conclusively through a blood test and thorough medical examination. But knowing whether they're likely to is very useful information, because it lets you determine whether it's worth putting in the extra effort to diagnose it conclusively. (Similarly, even if they carry the genetic marker, they might not be having a sickle-cell crisis, and it could be a blood clot or some other medical condition. But it's pretty damn likely.)

It's a fallacy to believe that just because the data you're working with can't tell you everything, it tells you nothing. Rather, you should recognize the limitations of what you know, and use them to determine what else you need to know. Race tells you something. It doesn't tell you a whole lot, because there's a lot of individual variation within a race. But that doesn't mean it tells you nothing, either.

Actually, there is an objective test for "black". It uses an instrument called a spectrophotometer.

Which didn't work: http://en.wikipedia.org/wiki/DNAPrint_Genomics http://dash.harvard.edu/handle/1/3008240

It doesn't even pass the smell test. Seriously: would Obama (who's turning into quite the counterexample here) show up "black" or "white" on that test? If the answer isn't "both" (it has to be, as he's almost literally 50/50) then the test can't work. If it is "both", then what meaning did "black" have again as a genetic grouping?

People insist on misinterpreting me here. I'm not saying that it's impossible to tell if someone has ancestry from africa or east asia or wherever. I'm saying that blocking real people (i.e. not members of an isolated subgroup with pure ancestry) up into a "race" like "asian" or (especially) "black", doing studies on them (like an IQ test) and arguing that this is "valid" because those groups are "genetically defined" is wrong. It's bad science. Please stop.

Thanks for the links. Here's my thoughts, take them or leave them: First, it's a big leap to go from the Harvard article's "here are theoretical issues with this test, not knowing any specifics of how it works" to "this doesn't work." There appear to be two components to the test, a genetic admixture, and predicted phenotypic characteristics that manifest with specific allele groupings, within a certain threshold of accuracy. Genes are not all equally heritable, there are dominant characteristics, so it can't be said that if someone is 50% one ethnicity and 50% another that you can't make any predictions about their appearance. This doesn't represent a rigid genetic definition of "race" I agree, but if it works for its intended purpose (matching phenotypic characteristics we generally associate with race to a genetic makeup) it opens the door to doing a blood test, finding someone's peak intelligence (assuming intelligence is heritable and measurable) according to some metric, and, possibly, associating that with a heritage/ethnicity/declared race, again within a certain accuracy threshold. (On the other hand, it may not extend all the way to heritable intelligence, or, the blood test might not even work for its intended purpose.) I also agree this would never mean that someone could say to an individual "you are a member of this race, therefore your intelligence peaks at IQ X" but you could use it to make predictions about an ethnic group in the aggregate.

I tried to qualify my statements here very carefully. I'm not claiming a strict genetic definition of race. I'm also not defending this specific blood test, I only know about it from that Wired article. But the theoretical possibility of what I have mentioned seems to exist, if that test or one like it actually works. Or am I mistaken?

> The idea of classifying people like that doesn't work genetically. [...] Basically, "race" is a cultural distinction.

No, it's not, and classifying people "like that" makes sense.

> In one of the most extensive of these studies to date, considering 1,056 individuals from 52 human populations, with each individual genotyped for 377 autosomal microsatellite markers, we found that individuals could be partitioned into six main genetic clusters, five of which corresponded to Africa, Europe and the part of Asia south and west of the Himalayas, East Asia, Oceania, and the Americas


These guys http://genome.cshlp.org/content/19/5/815.long even have a picture http://genome.cshlp.org/content/19/5/815/F2.large.jpg

I think you're aggressively agreeing with me.

Please find me the "races" on that chart. I don't see any. This is a chart of "genetic clusters". Which one does, say, Barack Obama (most famous mestizo I could think of, but frankly you could put almost all of the non-white population of the US into similar buckets) belong to? He doesn't fit. Most people don't fit. (Editted to point out: it's specifically a study of a small number of individuals of "pure" background.) Yet, and this is important, he does have a "race". Everyone, including himself, agrees that he's "black".

So where does "black" go on that chart? It doesn't. So "race" is non-scientific.

> So where does "black" go on that chart?

In the cluster on the left.

Yikes... Did you actually read what I wrote? Or the study? You're completely misinterpreting it. It's not saying that "everyone belongs to a genetically determined race", it's simply saying (duh) that these genetic clusters can be measured, and it shows some relationships between them that might be indicators for recent shared ancestry, etc...

This is specifically a chart of individuals with "pure" ancestry. People with mixed ancestry (i.e. almost all of us) have no spot on it. It doesn't tell us anything about our "race".

To get back to the example. If "blacks" belong on the bottom left than Obama (with his northern european mother) isn't black. So either he has a "race" or he doesn't. Which is it?

Stop thinking about "race" as a measurable thing, it isn't.

There are clear, genetic clusters corresponding with what we generally call races.

The fact that some people, mostly from the former European colonies, won't perfectly fit doesn't change that. The fact that this distinction is blurred, emphasized, or altered for political reasons doesn't change that. The fact that outward features, which are often used as proxy for the underlying genetics, can sometimes be misleading doesn't change that.

Also, I don't think "almost all of us" or even most of us wouldn't fit into those clusters. Do you have a source?

I understand that Obama is not exactly technically black; that legal, political or self-identified race may not align with those clusters or even known ancestry but it doesn't invalidate the concept. Just like there are people who are legally blind, and a subgroup who really can't see anything.

Maybe I should have said "genetic clustering" instead of "race".

Out of curiosity, when you say "people have been interbreeding like rabbits", does that mean that you believe that rabbit "breeds" are also a cultural distinction?


Are you trolling? No. Animal breeds are pure, because their reproduction is controlled and only the desired stock is used. "Races" aren't like that at all. Saying something like "blacks have low IQ" is completely unscientific because the people you are labelling "black", unlike animal breeds have little to no genetic relation. I'm too lazy to look this up, but the median "african american" has less than half of their ancestry from subsaharan africa.

So please, don't say things like "race is genetically determined". You're right that a "genetic cluster" or "ancestral group" is better defined. But those IQ results weren't corrected for that, so again: non-science.

Two wonderful companions to this article are "Thinking Intelligence is Innate Makes You Stupid" http://lemire.me/blog/archives/2007/12/03/thinking-intellige... and (especially) Cosma Shalizi's article on the malleability and heritability of IQ http://cscs.umich.edu/~crshalizi/weblog/520.html

Links to information about the book under review, Are We Getting Smarter?: Rising IQ in the Twenty-First Century by James R. Flynn:



(The three expert reviewers shown on Amazon are all very impressive researchers on human intelligence in their own right, so their joint endorsement of Flynn's book carries a lot of weight for people like me who follow the research.)

Here is what Arthur Jensen said about Flynn back in the 1980s: "Now and then I am asked . . . who, in my opinion, are the most respectable critics of my position on the race-IQ issue? The name James R. Flynn is by far the first that comes to mind." Modgil, Sohan & Modgil, Celia (Eds.) (1987) Arthur Jensen: Concensus and Controversy New York: Falmer.

AFTER EDIT: Replying to another top-level comment:

I don't understand how anyone could not have an emotional response being told 'your IQ is x'.

People have emotional responses to most statements about themselves that they think are overall evaluations. Some of those emotional responses are more warranted than others. Devote some reading time to the best literature on IQ testing (besides the book under review in this thread, that would include Mackintosh's second edition textbook IQ and Human Intelligence


and the Sternberg-Kaufman Cambridge Handbook of Intelligence,


both recently published). Any of these books will help readers understand that IQ tests are samples of learned behavior and are not exhaustive reports on an individual's profile of developed abilities.


Discussion of heritability of IQ, a reliable indicator of how much discussants read the current scientific literature on the subject, has ensued in some other subthreads here. Heritability of IQ has nothing whatever to do with malleability (or, if you prefer this terminology, controllability) of human intelligence. That point has been made by the leading researchers on human behaviorial genetics in their recent articles that I frequently post in comments here on HN. It is a very common conceptual blunder, which should be corrected in any well edited genetics textbook, to confuse broad heritability estimates with statements about how malleable human traits are. The two concepts actually have no relationship at all. Highly heritable traits can be very malleable, and the other way around.

Johnson, Wendy; Turkheimer, Eric; Gottesman, Irving I.; Bouchard Jr., Thomas (2009). Beyond Heritability: Twin Studies in Behavioral Research. Current Directions in Psychological Science, 18, 4, 217-220


is an interesting paper that includes the statement "Moreover, even highly heritable traits can be strongly manipulated by the environment, so heritability has little if anything to do with controllability. For example, height is on the order of 90% heritable, yet North and South Koreans, who come from the same genetic background, presently differ in average height by a full 6 inches (Pak, 2004; Schwekendiek, 2008)."

Another interesting paper,

Turkheimer, E. (2008, Spring). A better way to use twins for developmental research. LIFE Newsletter, 2, 1-5


admits the disappointment of behavioral genetics researchers.

"But back to the question: What does heritability mean? Almost everyone who has ever thought about heritability has reached a commonsense intuition about it: One way or another, heritability has to be some kind of index of how genetic a trait is. That intuition explains why so many thousands of heritability coefficients have been calculated over the years. Once the twin registries have been assembled, it’s easy and fun, like having a genoscope you can point at one trait after another to take a reading of how genetic things are. Height? Very genetic. Intelligence? Pretty genetic. Schizophrenia? That looks pretty genetic too. Personality? Yep, that too. And over multiple studies and traits the heritabilities go up and down, providing the basis for nearly infinite Talmudic revisions of the grand theories of the heritability of things, perfect grist for the wheels of social science.

"Unfortunately, that fundamental intuition is wrong. Heritability isn’t an index of how genetic a trait is. A great deal of time has been wasted in the effort of measuring the heritability of traits in the false expectation that somehow the genetic nature of psychological phenomena would be revealed. There are many reasons for making this strong statement, but the most important of them harkens back to the description of heritability as an effect size. An effect size of the R2 family is a standardized estimate of the proportion of the variance in one variable that is reduced when another variable is held constant statistically. In this case it is an estimate of how much the variance of a trait would be reduced if everyone were genetically identical. With a moment’s thought you can see that the answer to the question of how much variance would be reduced if everyone was genetically identical depends crucially on how genetically different everyone was in the first place."

The review article "The neuroscience of human intelligence differences" by Deary and Johnson and Penke (2010) relates specifically to human intelligence:


"At this point, it seems unlikely that single genetic loci have major effects on normal-range intelligence. For example, a modestly sized genome-wide study of the general intelligence factor derived from ten separate test scores in the cAnTAB cognitive test battery did not find any important genome-wide single nucleotide polymorphisms or copy number variants, and did not replicate genetic variants that had previously been associated with cognitive ability[note 48]."

The review article Johnson, W. (2010). Understanding the Genetics of Intelligence: Can Height Help? Can Corn Oil?. Current Directions in Psychological Science, 19(3), 177-182


looks at some famous genetic experiments to show how little is explained by gene frequencies even in thoroughly studied populations defined by artificial selection.

"Together, however, the developmental natures of GCA and height, the likely influences of gene–environment correlations and interactions on their developmental processes, and the potential for genetic background and environmental circumstances to release previously unexpressed genetic variation suggest that very different combinations of genes may produce identical IQs or heights or levels of any other psychological trait. And the same genes may produce very different IQs and heights against different genetic backgrounds and in different environmental circumstances."

"did not find any important genome-wide single nucleotide polymorphisms or copy number variants, and did not replicate genetic variants that had previously been associated with cognitive ability"

It's worth making another point here - just because there is no single gene for a trait does not make in unheritable, and just because a trait is genetic does not mean there is a single gene for it.

Eye color, for example, is clearly a genetic trait, but may be controlled by as many as 16 different genes. Race is also genetic, but really is shorthand for variation in hundreds, maybe thousands of genes.

It's well-established that intelligence is polygenic. That doesn't mean it's not genetic - if everybody had the same genes, ~80% of the variation in intelligence would be eliminated. It also doesn't mean that there's a single genetic switch we can throw to design a master race of human geniuses. It means exactly what it says: that there are some combination of genes that interact together to produce ~70-90% of the variance in the measured quantity that we label "intelligence".

"Race is also genetic, but really is shorthand for variation in hundreds, maybe thousands of genes."

There's a subtlety in your statement that I think will be lost on too many people, even more so given the juxtaposition with the statement about eye color. So at the risk of sounding pedantic...

Race is not a trait like eye color. Variations in the human gene pool are not evenly distributed geographically or across ethnic groups for a number of historical reasons. Many of these genes manifest in our physical appearance. But there is no countable number of races. Dividing humanity into 3, 4, 5 or even a hundred races is totally artificial. All you have to do is walk from Europe to SE Asia, or Europe to Africa via the middle east and you will see a gradual change, a gradient for each of the observed physical differences.

So description of "race" as a "shorthand" is spot on. Sadly it is a poor shorthand because most everyone conceive of race as discrete types of humans.


If you have a broad enough cultural background, eye color is not a simple discrete trait either.

I was eavesdropping on the conversation behind me on the bus today:

"What color would you describe your eyes as?" a guy asks.

"Green-ish. Something like that," a girl answers.

"Good, you didn't say hazel. A bunch of people would've called them that."

And then followed a whole long discussion about how you can basically perform hierarchical agglomerative clustering on humanity's words for colors, if you follow the words linguistically back through a few thousand years. Apparently the first split happened between light & dark, and then broad colors like "blue/green" (as a single color) split off, and then modern languages broke blue & green into separate colors.

Some folks break them down even further, into "cerulean" and "turquoise" and "aquamarine" and "royal blue". I've heard (from sources other than the bus conversation) that women actually have significantly more color words in their vocabulary than men do; they make distinctions where men don't.

So eye color is a shorthand too. Some people just say "light" or "dark". Others say "brown" or "blue". Still others will break it down into "black", "brown", "blue", "green", and "hazel". Once in a while you'll get a poetic type who'll say "Eyes the color of a roiling sea, as you catch the last glimpse of sunlight before a storm rolls in."

Bringing it back on topic, intelligence is a shorthand as well. It stands for a bunch of directly observable characteristics, but which characteristics vary depending on who you ask. Some people think an intelligent person is one with a high IQ who always does well on standardized tests. Others think it's someone who accomplishes great things in the intellectual realm, another Tesla or Einstein. Still others define it as a talent, and claim there're multiple intelligences, each in one desirable realm.

Perhaps the meta-lesson isn't about race or eye color or heritability at all, it's to drill down and ask what we actually mean by such broad characteristics. When you make a statement such as "IQ has a heritability of 0.8", you're making a very specific statistical assertion (though even that's not ironclad: which IQ test?). But whether that lines up with the statement of "Intelligence is largely genetic" depends on what you mean by "intelligence" and "genetic", both of which are very broad concepts that hide a lot of subtlety.

On intelligence being a shorthand, I would add that some people define it as having an extremely good memory.

There are many people with an extreme capacity for memorizing facts and images. It is said that one of our national poets, Eminescu, wasn't able to forget anything.

By this classification, many people are and were smarter than Einstein, who apparently couldn't remember his son's or wife's birthday, or know how many feet are in a mile (although this may be just folklore). Einstein also started to speak a lot later than normal kids, at 3 years old by his own testimony and performed badly in his first years of elementary school, with his parents being warned that he had a mental disability.

And yet he was able to come up with the relativity theory, which goes to show that intelligence is indeed relative.

> On intelligence being a shorthand, I would add that some people define it as having an extremely good memory.

That's the old popular definition of intelligence, the "walking encyclopedia" model. But books, and more recently computers, have greatly reduced the value of that kind of intelligence, by being better at it than any person.

Now that we have more facts at our fingertips than we can possibly absorb, a different kind of intelligence is (a) more valuable, and (b) more likely to arise from the interaction between a human and an inexhaustible source of facts (like a computer) -- the ability to synthesize new ideas out of old ones.

In olden times, simply being able to recite facts was prized, but books and computers can now do that more efficiently -- consider that a computer recently prevailed in "Jeopardy" against a selection of very good human contestants.

The new indicator of intelligence is the ability to come to an original conclusion based on a mass of accumulated facts. Because fact collecting is more easily done by a computer, and because of the value of the ability to create new ideas out of old ones, this new meaning for intelligence may well become dominant by way of natural selection.

Here's an example I heard recently while reading about planetary science:

1. Jupiter's moon Io has volcanoes, but it's too small for those volcanoes to have the same cause as those here (Io has long since lost the heat arising from its original formation). This means that many people were able to describe Io's volcanoes, but no one could explain them.

2. Io also has an elliptical orbit around Jupiter -- which means it moves closer to, then farther from, Jupiter, during each orbit.

Someone put facts (1) and (2) together and realized that it was Io's elliptical orbit, and the consequent huge flexure of tidal force within Io's solid mass, that's heating the moon and providing the energy source for the volcanoes.

It is this kind of intelligence that is recognized -- prized -- in the present and future: the ability to synthesize.

> or know how many feet are in a mile (although this may be just folklore)

I can believe that. He grew up in metric countries.

Indeed, it would seem that if human genetics aren't also changing at a lightning rate, the alternative explanation for the Flynn Effect would have to be that human beings are learning the particular skills called-for to take IQ tests "at a lightning rate".

Does that mean people are learning more skills in general? I don't think so. In fact, it doesn't seem like people are learning the skills on other standardized tests more quickly. What is it about IQ tests that allows scores to increase like this?

I have no idea what is the author of the articles opinion, and what is from the book being reviewed. I'm not even sure what the title of the book being reviewed is.

I'm glad I wasn't the only one completely confused. I have no idea what he was trying to say, I can't imagine what his book is like.

>For this to happen, evolution would have had to have accelerated to light speed.

What? No... no. There are plenty of ways that intelligence could have dramatically increased since the '30s without any evolutionary effects.

And still IQ is very good at predicting various life outcomes: probabliity of being arrested, income, number of children.

Group differences in IQ do exist, and Flynn effect does not make them go away. Flynn effect increases scores across the board, it does not equalize different groups.

Black people in US have lower average IQ than white people do, Asian people have higher average IQ. The reasons for this are many, but genetics certainly comes into play: IQ is heritable.

Trying to explain away group differences by "culture" is mostly bad science - trying to make the facts fir your desired conclusions.

Key takeaway from the article:

Flynn’s interpretation overturns one of the most ­dangerous myths of IQ research — that blacks have been shown to be fundamentally less intelligent than whites. With what seems to me to be a series of cast-iron statistical analyses, he shows that this has, in fact, never been proved ... What the evidence actually shows is that racial differences, once all external factors are removed (primarily the social and cultural context of the testees), seem to be almost undetectably small.

I personally don't believe there to be real genetic differences in this context, but that conclusion doesn't seem to preclude there being differences in social and cultural predispositions for different races, then there would still be a direct causal relationship between race and intelligence.

As I understand the book is not out yet, so I still have to see these "cast-iron" analyses. Surely it would be interesting to have a look.

The problem that I see here is that by removing all social and cultural context we will lose some genetic information as well. It is very hard to measure influence of genetics on social or cultural outcomes, but it definitely does exist.

The twin adoption studies disprove this. Adult twins resemble each other more than anyone else, and resemble their adoptive families no more than they resemble families selected at random.

I have not read Flynn's book yet, but he will have to do something amazing to explain away the twin adoption studies.

I have not read Flynn's book yet, but he will have to do something amazing to explain away the twin adoption studies.

Do read his book. You will surely learn something. The references to recent publications on heritability that I posted as a second edit to my comment at the highest comment level in this thread (currently the top comment in the thread) include several publications by researchers who have worked on the Minnesota Twin Study and other twin studies. I join a weekly journal club during the school year with most of the researchers on the Minnesota Twin Study (one of whom, coincidentally, is my fifth cousin) and I rely on them to keep me up to date with what the latest research shows.

And what the latest research shows, after we look at all the twin study findings, is fully consistent with HN user Steko's quotation from the review of James R. Flynn's new book, the parent comment to your comment.


Tyler Cowen [1] refers us to Jay Joseph [2] who refers us to other critics of "twins reared apart" ("TRA") studies:

Critics, however, have pointed to several key methodological problems with TRA studies (TRA study critics include Farber, 1981; Joseph, 2001, 2004, 2010; Kamin, 1974; Kamin & Goldberger, 2002; Lewontin, Rose, & Kamin, 1984; Taylor, 1980). These problems include (a) the doubtful “separation” of twins, who frequently grew up together and had contact over much of their lives, (b) similarity bias in the methods of MZA identification and recruitment, (c) the questionable status of “intelligence” and “personality” as valid and quantifiable constructs, (d) the failure of the MISTRA researchers to publish or share raw data and life history information for the twins under study, and (e) the impact that the researchers’ bias in favor of genetic interpretations may have had on their results and conclusions.

and continues:

While these and other issues are important, the main problem with TRA studies such as Bouchard’s MISTRA is clear: the investigators used the wrong control group (MZTs). By using MZTs as controls, they failed to control for several key environmental factors shared by both MZA and MZT pairs (see Joseph, 2004; Rose, 1982). Environmental influences shared by both MZAs and MZTs include but are not limited to the following:

• They are exactly the same age (birth cohort).

• They are always the same sex.

• They are almost always the same ethnicity.

• Their appearance is strikingly similar (which will elicit more similar treatment from the social environment).

• They usually are raised in the same socioeconomic class.

• They usually are raised in the same culture.

• They shared the same prenatal environment.

• Most studied pairs spent a certain amount of time together in the same family environment, were aware of each other’s existence when studied, and often had regular contact over long periods of time (Farber, 1981; Kamin, 1974).

So maybe twin studies aren't the slam dunk they are often presented as.

[1] http://marginalrevolution.com/marginalrevolution/2011/02/wha...

[2] http://jayjoseph.net/yahoo_site_admin/assets/docs/Claims_and...

Also referenced by Cowen:



And yet its clear you did not read the article.

No, I agree with this. There was obviously nothing wrong eugenics movement 100 years ago. And obviously minorities get arrested more, have lower income, and a lot of children because of their extremely low IQ as opposed other social forces.

See the difference is you are talking out of your ass, whereas Flynn has a book filled with verifiable statistics.


Christopher Langan.

These people aren’t any less intelligent than the researcher — their minds just work differently. They focus on the practicalities they know rather than hypothetical possibilities.

That's going to need some explanation. First off, I can see how the question itself is abstract, about a place they have never been, but "no camels" sounds extremely concrete to me. Second, how is ignoring information anything other than a lapse in intelligent thought?

>> These people aren’t any less intelligent than the researcher — their minds just work differently. They focus on the practicalities they know rather than hypothetical possibilities.

> That's going to need some explanation. First off, I can see how the question itself is abstract, about a place they have never been, but "no camels" sounds extremely concrete to me. Second, how is ignoring information anything other than a lapse in intelligent thought?

The underlying point is valid, but it was not explained well in the article.

The point is that "extremely concrete" is always relative to language. For example, in the bible, "40 years" meant something like "a long long time", not 40 literal years. Likewise, a "foot" today does not mean a concrete human foot (although it originated as a particular one). A more annoying example today is that "literally" no longer means "literally" ("I literally died when ...").

To be specific about this example, it is possible that saying "There are no camels in Germany; how many camels are there in city X?" is interpreted in different ways in different languages and cultures. Perhaps "there are no camels" means "camels do not naturally live in that area", but there could be camels brought there artificially, say to be in a zoo. And especially when asking "how many camels are there in city X?", the implication is that specific details about city X matter, for example if it has a zoo or not. The person being asked might try to guess if it has a zoo based on the city size etc.

Also worth noting that the question is of the form of a classic logic puzzle. That sort of thing is part of the Western cultural tradition since ancient Greece. But other cultures have other traditions.

See also the philosopher Wittgenstein on "following a rule". No sentence in any language is ever so concrete that it cannot be interpreted in many ways.

Ah, I hadn't even thought of it being a phrasing that is hard to translate. Interesting idea.

I definitely agree. While it may be entirely true that the Flynn effect can be explained without any difference in what is being defined here as intelligence, I don't want anyone to write with the preconceived conclusion that there must not be any difference in intelligence, which it sounds like is the case with the statement you quoted.

You're missing the point. If you ask someone a question that expects them to think in a way foreign to them, it does not say anything about their intelligence if they have difficulty approaching it.

Think of the old "analytical" thinking questions companies used to give out like "how many golf balls can you fit in a bus", "how many high schools are there in America", etc.

Now, I'm not the smartest person but my peers and bosses consider me to be highly intelligent. When I first heard these questions, I was completely stumped. I mean, I've never really taken public transportation and I don't know really have a good idea of how many students go to a typical high school or even how large America is, so how was I supposed to know? However, the population cutoffs for high schools and the size of buses and golf balls are very concrete and well known. Does this show a lapse in my intelligence?

The examples you gave only have issues in not knowing the sizes of things. They have nothing to do with thinking in 'foreign ways'. If I show someone a golf ball and ask how many fit into a wagon I expect them to at least say "a lot". If they have math skills then I expect an order-of-magnitude estimate.

If you don't know the sizes, then the test-maker has failed you. If you know the sizes and still can't answer, then yes it is a lapse in intelligence.

Can you give me an example of a problematic question that isn't caused by using unfamiliar nouns?

This isn't exactly the same thing as "no camels" but it feels like it's in a similar completely-out-of-your-frame-of-reference ballpark: People thought all-touchscreen devices with no keypad would be useless as phones—they didn't see how the inconvenience of punching numbers in on a touch screen without tactile feedback could be greatly outweighed by other stuff the large touchscreens would end up enabling. Yet it would be ridiculous to say the reason anyone failed to initially grasp the possibilities was a lack of intelligence.

I imagine that being told "there are no camels in Germany; how many camels are in this German city?" simply sounded ridiculous to the rural Russians. And so I assume that with no background in abstract reasoning or "word problems" where you're supposed to rely on just the information presented in the problem, they fell back on what they knew about cities: they're places with camels. Imagine if someone came to you from another country and said something like "we don't have people in our cities. But Atlantis is our biggest city. So how many people do you think live there?" It would sound meaningless.

As far as the phone example, that's just disagreeing about tradeoffs. These people could easily see the uses, they just thought buttons were better.

Honestly, with the camel example, I think it was a problem of asking a really dumb question without explaining that the question might be so dumb. If you ask me the Atlantis thing out of the blue I might give a weird answer. But if you specifically assure me that you're not trying to trick me in your Atlantis scenario and you just want to hear my answer to the question then I'll say no people and wonder if it's abandoned or filled with robots or cats.

Well, if you know how to solve the problems I mentioned, you would be aware that they have nothing to do with knowing the sizes of things. To solve these problems, you must think practically and state assumptions about how much you expect the average sizes to be and how much in comparison. For example, the way to solve the high school question is start off with assuming the amount of people living in is about 300-400 million range and that maybe 10-20% of those are old enough to be attending high school. And then you go to estimate the amount of high schoolers in each state and whether that state was small, medium, or large, etc. Those problems are only about approaching a problem with those sorts of practical, reasoned thoughts in your head. To alot of people, including myself, this way of thinking is very foreign. However, if you were to ask me to design a database, I'd have no problems. This discrepancy does not show a lapse in intelligence.

Also, "a lot" is obviously not an acceptable answer if "I don't know, there should be some there" isn't for you.

> Can you give me an example of a problematic question that isn't caused by using unfamiliar nouns?

Maybe if I tried really hard? But that's the point I'm contending. A lot of IQ and standards test use unfamiliar nouns/concepts/abstractions to test intelligence, so does a certain group of people struggling with them show their lack of knowledge?

nothing to do with knowing the sizes of things

You yourself listed the big problems of not knowing how many students go to a school or how large America is. All I'm looking for in answer to that question is taking the number of people in America [pre-knowledge unless the test-maker screwed up], guessing what percent are in high school [pre-knowledge unless the test-maker screwed up], and dividing the size of a high school [pre-knowledge unless the test-maker screwed up]. It's all about figuring out how to combine knowledge to get an answer. Which is also what you use a relational database for so I don't see how you can do one and not the other.

Also, "a lot" is obviously not an acceptable answer if "I don't know, there should be some there" isn't for you.

Well I'm only going to accept "a lot" as a final answer if they have no math skills at all. That depends on the culture. But it shows a basic idea that yeah, it takes a whole bunch of golf balls to fill it up. Just like saying "no camels means no camels" indicates an understanding of the dumb-but-simple question. Saying "some camels" is the answer I won't accept.

It's all about figuring out how to combine knowledge to get an answer. Which is also what you use a relational database for so I don't see how you can do one and not the other.

Which is exactly my point, again. It's not that I can't do both. It's that, although both questions take similar intelligence, one of them is phrased in an unfamiliar way. I start off disadvantaged in the former question because my lack of familiarity with what the "correct" answer should look like. With the latter, I know how to begin thinking and answering. Yet, an IQ only provides one of these options so if I got the one I was not familiar with, I would score low. My point is that is not a sign of a lack of intelligence.

Just like saying "no camels means no camels" indicates an understanding of the dumb-but-simple question. Saying "some camels" is the answer I won't accept.

But to understand a question, the premise of it has to make sense to you. For my example, I can understand the question because I'm aware that there is a real solution. In the example from the article, to ask farmers who only know about cities with camels about the camels in a city where there are no camels doesn't make sense to them. It's an unnecessary abstraction and just shows that they haven't experienced a situation rather than that they can't answer a simple question.

To me it's almost as if someone asked me "in a math system where 1 * a is not a, what is 1 * a?" or "what is 2 + 2 for arbitrarily large values of 2?" Simplicity is subjective.

>To me it's almost as if someone asked me "in a math system where 1 * a is not a, what is 1 * a?"

Hmm, I think it's more like "a math system where 1 * anything is 1". It's baffling to my understanding of math but it still fully explains itself. "Like multiplication, but different" "like a normal country, but without camels" I have no idea why it's this way but I can still make use of it and answer the question.

Anyone interested in this topic should read the primary research papers.

The pattern of differences in IQ test answers between generations is not congruent with the pattern of differences between individual who do better and worse on average within generations -- at least according to the few studies which have looked at this question. For this reason, we can infer that the generational changes in IQ test scores are not changes in the same underlying factor that causes differences in performance within a generation. If we call the factor that causes within-generation differences in IQ test scores intelligence, then what differs between generations isn't intelligence. In other words, the Flynn effect is something other than what it might appear at first glance. It's still something of a mystery.

Multi-group confirmatory factor analysis can be used to demonstrate this, or you can just look at the correlation matrices.

OT: Just me, or does browser zoom not seem to increase font size for this page in Safari and Chrome?

Super annoying, I had to read it in Instapaper just to cope.

Unrelated to the content, when I use Command-plus to increase the font size on this blog (in Chrome, at least), the font doesn't grow.

Which means I can't read it, because my eyes suck.

"contrary to widespread assumptions, no clear link between nutrition and IQ has been found."

Someone call up Paul Krugman and tell him that iodine deficiency doesn't actually cause mental retardation.

To not know the answer to "there are no camels in Germany so how many camels do they think there are in B, a specific German city? " is not a cultural difference, to think that other cultures are seriously that dumb is more a statement on ones self than anything else.

This is similar to statements engineers sometimes make that the Chinese are good copiers but can't innovate.

No, cultures are the same as everyone else. They have humour, art and like to tinker and have in jokes. If they don't publicly innovate it's more likely it's not economical in that environment yet.

The fact 'camels' was used has strong undertones to me, if this was an actually a study I'd be interested to know.

> No, cultures are the same as everyone else. They have humour, art and like to tinker and have in jokes.

Oh, cultures share lots of features. But I've been in a few. Even countries as geographically close as Britain and Germany have quite a few differences.

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