I don't know much about IQ. In the most extreme case, of dissimilar education, the different was about 15 points. Is that a lot? What does that mean to laypeople?
As a parent of identical twins watching them develop and grow is fascinating. I do wonder at times how much of it is due to going through every single life stage together but then again there are times where that bond seems to go beyond environment. There was a sobering but very interesting documentary on identical twins called Three Identical Strangers, if you are interested in this type of stuff it's a good watch.
Of course. IQ tests measures nothing more than the ability to pass an IQ test, which is proxied by a lot of things such as western culture, education, propensity to cram tests, etc.
An interesting tidbit in the nature vs. nurture debate is that nature and nurture interplay in ways you might not expect. For instance, height is approximately 90% heritable in the United States -- but this does not mean that in a vacuum height is mostly genetic. It means that in the United States nutrition has mostly been solved (and yes, even the "food insecure" in the US rarely lack for the actual calories which would impact their height -- food insecurity causes other problems) and therefore the only real differences that can remain are the genetic differences.
It might be useful to look at any twin study through this lens; if we know for sure the genes are the same and nature is off the table, how much variance remains?
In particular, see the third chart, "GREML-WGS heritability estimates," which shows that heritability for height is pretty much the same when they try to adjust for environment in different ways, while the estimates for IQ vary a lot.
Gusev seems convinced that some environmental effect is inflating heritability estimates for IQ that are based on twin studies.
That's not mostly solved, that's tens of millions of truncated, immiserated lives. Of course calorie quality differences are important to child development.
>and therefore the only real differences that can remain are the genetic differences.
Incidence of undiagnosed digestive and sleep disorders, like celiac disease and sleep apnea, respectively. "Catch-up" growth occurs almost universally after treatment starts, which means that the growth trajectory was lower than the "genetic potential", and likely remains so for children who can't access treatment.
Multiply across any number of silent or untreated disorders, sensitivities, or insufficiencies.
Adult height also isn't 90% heritable in the US. It only reaches that high a percentage of heritability in studies involving closely-related populations. In which case, of course; in populations with low genetic and cultural diversity and moderate or high variability, small differences are magnified.
> Of the 87 pairs, 52 experienced a similar type and duration of schooling within a similar location. In fact, 25 of these pairs attended the same school for some period of time. Analysis revealed that ‘Educationally Similar’ TRA pairs have an ICC of 0.87 ± 0.02 (n = 52)
So this study has 87-52-25=10 data points? Am I reading this correctly? Quite the reach to conclude what the article claims, if so.
IQ testing was recently found to be highly driven by response to difficult challenges, and could be influenced significantly by just tuning the rewards for participants doing well. Which suggests that measuring iq is a pretty fraught science, if you are trying to draw conclusions about heritable intelligence...
If you give the same test to different people under completely different reward conditions, nobody is going to be surprised when the results are different.
IQ tests are far from perfect, but when the same test is administered to different groups under the same conditions it can be reasonable to draw some signal out of the differences between groups.
Generally in a study like this the people administering the test wouldn't even know which group each person belonged to.
It's common knowledge that IQ tests aren't perfect, but your linked paper doesn't debunk their usefulness in a study like this. Not unless the researchers unblinded themselves and offered one group a large reward, which would be a much bigger problem than the use of IQ tests.
There are two different kinds of IQ tests: convergent and divergent. Convergent tests are more common and test either knowledge or pattern matching. These tests are called convergent because they are a center of truth and conformance to that truth is the measured performance criteria.
Divergent tests measure the individual's creativity and abstract reasoning. The source of truth is the quantity of diversity of results submitted by the participant.
The implicit success criteria for convergent testing is reading comprehension. A person with dyslexia, for example, will perform worse on these tests irrespective of their learning speed, learned knowledge, intellectual curiosity, or creativity. This is a form of bias. Other forms of bias include memorization of terms, such as SAT preparation.
To further complicate things these measures typically only account for academic intelligence. Other forms of intelligence include social intelligence, spatial intelligence, creativity, conscientiousness, and so forth. In the concept of multi-dimensional intelligence, which is what is actually addressed in practice in the real world after high school, academic intelligence alone has very little benefit. Its like height in basketball where after 6.5ft all other factors become more important for all participants.
> A person with dyslexia, for example, will perform worse on these tests irrespective of their learning speed, learned knowledge, intellectual curiosity, or creativity. This is a form of bias.
No, it's what they were designed to do - help identify people that may need specialized help because issues like learning disabilities.
> To further complicate things these measures typically only account for academic intelligence. Other forms of intelligence include social intelligence, spatial intelligence, creativity, conscientiousness, and so forth.
The two major IQ tests (Stanford Binet and Wechsler) test visual-spatial reasoning, abstract reasoning, verbal and nonverbal reasoning, working memory, processing speed, inductive/deductive reasoning, attention, concentration, etc.
These tests, if properly administered (individually in person by a professional) work well for figuring out who in school needs extra attention or requires further evaluation. Their use beyond that is questionable.
I don't dispute the differences in intellectual capacity between people but IQ tests are like weight lifting contests between people who didn't train to lift weights.
I don't understand why the scientific community keeps using methods that are so flawed. Perhaps it's due to my own lack of information.
The only way I could see IQ tests being a valid measurement of intellectual capacity is if participants were brought to the same level of knowledge and skills, and then were made to train for the IQ test using the exact same means, and even then cultural and language barriers must be accounted for.
Even if these twins have an identical intellctual capacity and they both had the same exact education, and same exact grades, that still doesn't mean they applied and exercised their brains in the same way for the questions of the IQ tests.
IQ tests to measuring intellectual capacity (instead of knowledge level) are like polygraphs to mesasuring truthfulness in terms of accuracy.
For measuring strength, i stand by my earlier correlation with weight lifting. If two people can dead-lift 500lbs, I only know that both participants are have reached that level of strength. What I don't know is how much effort each participant put into getting to that level of strength, which would tell me their natural muscular capacity per effort. IQ tests deceptively seem like they tell you what someone's capacity for intellect is, but they only tell you where that person is right now. Maybe that person worked hard and the score is their max, maybe the person rarely applies their brain to demanding tasks and this is their mid-level capacity.
My point is,it isn't just education or just genetics, it is also personality, effort, motivation. For all I know,someone with double-digit IQ score can work out their brain for a year and hit genius level. Choice. Can a person choose to be a literal idiot and succeed? Certainly, people choose to be incurious and ignorant all the time. Women can body-build and be as strong as many regular men for example. But simply because of a hormone difference, they have to work out a lot more than men to reach the same level of muscular strength. And men who never work out can be as weak as women who never work out.
There is also the question of brain development. Maybe the effort you put has different effect depending on age. small efforts at a young age at applying your brain might have huge impacts, where as if you're a teenager or an adult, applying the same effort might yield less results.
I mean, personally, if I tired, if I ate too much, or too little,if didn't get enough sleep, if I am distracted by something, if I'm unprepared and thus second-guessing myself, these are some of the things that throw me off wildly when taking exams. I've seen huge differences by simply getting enough sleep and calories.
There is no way that asking the same set of questions to to large population (even with control populations in place) can account for all the presumptions of the test.
Speaking of IQ, when I listen to interviews and podcasts of supposed high IQ people like Mark Zuckerberg and Elon Musk, I struggle to see signs of intelligence (not saying that they don’t have above average IQ). I find that these 2 have a hard time sifting through the noise (competing thoughts) in their head to get to want they want to say (the signal).
When I listen to Steve Jobs, I hear someone who has very strong ability to sift through noise. So Jobs couldn’t see engineering in a new way like Elon does but Elon couldn’t do what Jobs did either.
Regarding Zuckerberg, from what I’ve read he is the Bill Gates type where he has the traditional variant of high IQ, aka raw hardware/horsepower but lower on creativity/imagination side.
So intelligence seems to have different shapes and sizes.
Don't read this as a defense of Zuck or Musk, but some of the most brilliant people I've known sometimes had trouble getting thoughts out. It wasn't that they couldn't see their goal, but that how they thought of it was changing even as the words were leaving their mouths. Have you ever tried to explain while you were still working it out in your head? "See, it's kind of like A..., except that one part is closer to B, and that's interesting because, well, B and C have a relationship that's closer than A and C, so it might be more appropriate to say it's more C-like, except where A is..."
That didn't mean they were unintelligent. It meant that them trying to explain the flurry of ideas in their head was like me trying to type with mittens.
Of course, knuckleheads can also sound like that, but for different reasons. That kind of rambling doesn't imply that the speaker is a dumbass. It definitely doesn't guarantee that they're a genius.
There is something wrong with this article, possibly just copyediting mistakes but it makes me question the whole thing.
For example, check out this mess:
> “Unfortunately, there is one significant issue with the aforementioned data: schooling. Seeing as the majority of work to date includes only aggregate data, it is impossible to account. The first concerns small N: seeing as most publish studies only include a handful of TRA data, there is a lot of room for error and over.
Unfortunately, there is a largely unaccounted for confound in this aggregate data which may make generalized analysis questionable: schooling.”
Good catch. Additionally, one of the authors on this is just a student at UWisc, and the other author is also not a professional researcher but instead an author of popular books.
This is not an ad-hominum, but does put into question the statistical training backgrounds of both of these authors to accurate assess the data.
The language is consistent with ESL writing, in my experience.
The strange thing is that the corresponding author and the co-author appear to be english speakers, as far as I can tell. I googled the primary author and found a YouTube channel where someone by the same name speaks clearly about neuroscience. Maybe I'm looking at another person with the same name and middle initial who also happens to speak about neuroscience and brain development?
Outside of a fascination with Intellectual Supremacism, why are people so obsessed with the genetic basis of IQ scores?
Presumably one could do similar identical twin studies on half-marathon race times and SAT test scores. Does no one bother with those, because widespread awareness of half-marathon training regimens and SAT prep courses would spoil the (desired) illusion of some "innate superiority of blood" being measured?
Exactly, it is on of the least remarkable results that intelligence is partly heritable. Obviously intelligence is partly genetic, obviously your ability to run a marathon is also partly genetic. Why one has devolved into a bizarre case where so much effort is spent on the minute details of this question and the other is accepted basically as completely uncontroversial (given who is currently competing for top times at marathons it is basically inarguable) is very strange.
How about the fact that the human mind and genetics are simply fascinating and interesting topics. I would imagine that people don't care as much about running and high school testing because they are fairly niche interests relative to abstract thinking in general, something that almost everyone spends much of their life doing.
I don't know how many more nails in the coffin of heritable intelligence are needed before public policy capitalizes on the opportunity here. We have seen huge shifts in intelligence in places like Korea after armistice, in China after economic and cultural reforms, and in the U.S. after COVID and smartphones. We have seen that individual tutoring reliably creates extreme outliers from the examples of Avant-garde, Williams, Tao, Polgár, the Hungarian Martians, etc. Aside from disorders, any heritable differences can be easily dwarfed by environmental effects, and some disorders, like OCD, only magnify environmental effects.
It's always been an insane claim that knowledge can't help you utilize knowledge. It's just an excuse to be racist and classist. Everything around IQ is linear, dumb thinking, suitable for trying to reduce everything to a scalar. IQ is a good tool for figuring out whether your child has a physical issue with their brain development, or maybe a hearing problem.
There's nothing logical about brains; they work on heuristics built on reflexes and associations. Logic is something we learn through physically interacting with the world, and from sitting in class. As you learn it, your thinking about other things gets better. When you read great old Chinese philosophers like Mozi struggling but managing to make good arguments without syllogism, it's a reminder that syllogism is something that is invented. It survives because of its unreasonable effectiveness compared to considering what the ancient heavenly kings had done.
It also helps your soul to remember that a lot of people you're arguing with have no idea what a logical argument looks like. They think that an argument is when you try to shut the other person up. It's not their fault, they just literally don't know. They're not arguing in bad faith, they don't know what good faith looks like because the educational system has failed them.
The weighting of this study is strange. The difference of number of years of education maxes out at 1 point, while being raised in different locations and different school types are each given also 1 point. It seems unreasonable that going to school in London vs New York should be given a point here despite the average educational quality in both cities potentially being the same. This also means that someone with 4 years more education but from the same city is considered educationally similar, and it is impossible to achieve the "educationally dissimilar" metric (ED DIFF > 2) without one of the other two points. I feel therefore like there is some wordplay being done here by the term "educational differences." I think some readers will assume that "educational differences" means "educational quality," but only one metric out of the 3 is directly correlated to this. This said there does seem to be some correlation and that is interesting, as we would expect no difference between location, yet there does seem to be one. In my opinion the different location variable is likely to be measuring something aside from/in addition to education. Some education types would seem to be better than others eg. boarding school. Also worth noting that the "very educationally dissimilar" group is n = 10. This said, the authors do admit that "certain level of inference is involved with comparing pedagogies and curriculum" and "Readers are encouraged to re-score and re-analyze the data in additional ways not done here." I would try weighting location much less and not cap number of years of education at all, instead studying how the differences change as the number of years increases.
The way we raise our kids will have major differences in their IQ... Keep in mind there is a 9 point difference between those raised apart vs those raised together. This is not a comparison between those who receive special education efforts vs those who don't, I assume that would be much larger.
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[ 1.5 ms ] story [ 50.4 ms ] threadIt might be useful to look at any twin study through this lens; if we know for sure the genes are the same and nature is off the table, how much variance remains?
https://theinfinitesimal.substack.com/p/the-missing-heritabi...
In particular, see the third chart, "GREML-WGS heritability estimates," which shows that heritability for height is pretty much the same when they try to adjust for environment in different ways, while the estimates for IQ vary a lot.
Gusev seems convinced that some environmental effect is inflating heritability estimates for IQ that are based on twin studies.
Nature is not off of the table. We've just traded problems with calorie quantity to quality.
That's not mostly solved, that's tens of millions of truncated, immiserated lives. Of course calorie quality differences are important to child development.Incidence of undiagnosed digestive and sleep disorders, like celiac disease and sleep apnea, respectively. "Catch-up" growth occurs almost universally after treatment starts, which means that the growth trajectory was lower than the "genetic potential", and likely remains so for children who can't access treatment.
Multiply across any number of silent or untreated disorders, sensitivities, or insufficiencies.
Adult height also isn't 90% heritable in the US. It only reaches that high a percentage of heritability in studies involving closely-related populations. In which case, of course; in populations with low genetic and cultural diversity and moderate or high variability, small differences are magnified.
So this study has 87-52-25=10 data points? Am I reading this correctly? Quite the reach to conclude what the article claims, if so.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10990577/
IQ tests are far from perfect, but when the same test is administered to different groups under the same conditions it can be reasonable to draw some signal out of the differences between groups.
Generally in a study like this the people administering the test wouldn't even know which group each person belonged to.
It's common knowledge that IQ tests aren't perfect, but your linked paper doesn't debunk their usefulness in a study like this. Not unless the researchers unblinded themselves and offered one group a large reward, which would be a much bigger problem than the use of IQ tests.
There are two different kinds of IQ tests: convergent and divergent. Convergent tests are more common and test either knowledge or pattern matching. These tests are called convergent because they are a center of truth and conformance to that truth is the measured performance criteria.
Divergent tests measure the individual's creativity and abstract reasoning. The source of truth is the quantity of diversity of results submitted by the participant.
The implicit success criteria for convergent testing is reading comprehension. A person with dyslexia, for example, will perform worse on these tests irrespective of their learning speed, learned knowledge, intellectual curiosity, or creativity. This is a form of bias. Other forms of bias include memorization of terms, such as SAT preparation.
To further complicate things these measures typically only account for academic intelligence. Other forms of intelligence include social intelligence, spatial intelligence, creativity, conscientiousness, and so forth. In the concept of multi-dimensional intelligence, which is what is actually addressed in practice in the real world after high school, academic intelligence alone has very little benefit. Its like height in basketball where after 6.5ft all other factors become more important for all participants.
No, it's what they were designed to do - help identify people that may need specialized help because issues like learning disabilities.
> To further complicate things these measures typically only account for academic intelligence. Other forms of intelligence include social intelligence, spatial intelligence, creativity, conscientiousness, and so forth.
The two major IQ tests (Stanford Binet and Wechsler) test visual-spatial reasoning, abstract reasoning, verbal and nonverbal reasoning, working memory, processing speed, inductive/deductive reasoning, attention, concentration, etc.
These tests, if properly administered (individually in person by a professional) work well for figuring out who in school needs extra attention or requires further evaluation. Their use beyond that is questionable.
I don't dispute the differences in intellectual capacity between people but IQ tests are like weight lifting contests between people who didn't train to lift weights.
I don't understand why the scientific community keeps using methods that are so flawed. Perhaps it's due to my own lack of information.
The only way I could see IQ tests being a valid measurement of intellectual capacity is if participants were brought to the same level of knowledge and skills, and then were made to train for the IQ test using the exact same means, and even then cultural and language barriers must be accounted for.
Even if these twins have an identical intellctual capacity and they both had the same exact education, and same exact grades, that still doesn't mean they applied and exercised their brains in the same way for the questions of the IQ tests.
IQ tests to measuring intellectual capacity (instead of knowledge level) are like polygraphs to mesasuring truthfulness in terms of accuracy.
For measuring strength, i stand by my earlier correlation with weight lifting. If two people can dead-lift 500lbs, I only know that both participants are have reached that level of strength. What I don't know is how much effort each participant put into getting to that level of strength, which would tell me their natural muscular capacity per effort. IQ tests deceptively seem like they tell you what someone's capacity for intellect is, but they only tell you where that person is right now. Maybe that person worked hard and the score is their max, maybe the person rarely applies their brain to demanding tasks and this is their mid-level capacity.
My point is,it isn't just education or just genetics, it is also personality, effort, motivation. For all I know,someone with double-digit IQ score can work out their brain for a year and hit genius level. Choice. Can a person choose to be a literal idiot and succeed? Certainly, people choose to be incurious and ignorant all the time. Women can body-build and be as strong as many regular men for example. But simply because of a hormone difference, they have to work out a lot more than men to reach the same level of muscular strength. And men who never work out can be as weak as women who never work out.
There is also the question of brain development. Maybe the effort you put has different effect depending on age. small efforts at a young age at applying your brain might have huge impacts, where as if you're a teenager or an adult, applying the same effort might yield less results.
I mean, personally, if I tired, if I ate too much, or too little,if didn't get enough sleep, if I am distracted by something, if I'm unprepared and thus second-guessing myself, these are some of the things that throw me off wildly when taking exams. I've seen huge differences by simply getting enough sleep and calories.
There is no way that asking the same set of questions to to large population (even with control populations in place) can account for all the presumptions of the test.
When I listen to Steve Jobs, I hear someone who has very strong ability to sift through noise. So Jobs couldn’t see engineering in a new way like Elon does but Elon couldn’t do what Jobs did either.
Regarding Zuckerberg, from what I’ve read he is the Bill Gates type where he has the traditional variant of high IQ, aka raw hardware/horsepower but lower on creativity/imagination side.
So intelligence seems to have different shapes and sizes.
That didn't mean they were unintelligent. It meant that them trying to explain the flurry of ideas in their head was like me trying to type with mittens.
Of course, knuckleheads can also sound like that, but for different reasons. That kind of rambling doesn't imply that the speaker is a dumbass. It definitely doesn't guarantee that they're a genius.
For example, check out this mess:
> “Unfortunately, there is one significant issue with the aforementioned data: schooling. Seeing as the majority of work to date includes only aggregate data, it is impossible to account. The first concerns small N: seeing as most publish studies only include a handful of TRA data, there is a lot of room for error and over.
Unfortunately, there is a largely unaccounted for confound in this aggregate data which may make generalized analysis questionable: schooling.”
This is not an ad-hominum, but does put into question the statistical training backgrounds of both of these authors to accurate assess the data.
The strange thing is that the corresponding author and the co-author appear to be english speakers, as far as I can tell. I googled the primary author and found a YouTube channel where someone by the same name speaks clearly about neuroscience. Maybe I'm looking at another person with the same name and middle initial who also happens to speak about neuroscience and brain development?
Presumably one could do similar identical twin studies on half-marathon race times and SAT test scores. Does no one bother with those, because widespread awareness of half-marathon training regimens and SAT prep courses would spoil the (desired) illusion of some "innate superiority of blood" being measured?
Yes, and some of those have been done: SAT scores correlate very strongly with IQ.
There's nothing logical about brains; they work on heuristics built on reflexes and associations. Logic is something we learn through physically interacting with the world, and from sitting in class. As you learn it, your thinking about other things gets better. When you read great old Chinese philosophers like Mozi struggling but managing to make good arguments without syllogism, it's a reminder that syllogism is something that is invented. It survives because of its unreasonable effectiveness compared to considering what the ancient heavenly kings had done.
It also helps your soul to remember that a lot of people you're arguing with have no idea what a logical argument looks like. They think that an argument is when you try to shut the other person up. It's not their fault, they just literally don't know. They're not arguing in bad faith, they don't know what good faith looks like because the educational system has failed them.
That's actually probably a very difficuly topic: cam we devise a test that measures intelligence irrespective of education (i.e. training)?