I don’t see a good way to tell the difference between a low IQ score due to actually being less intelligent versus a low IQ score due to nurture-related reasons such as the following:
As the saying goes, “Life is an IQ test.” The predictive ability of IQ on income (and most other statistics of interest) is very similar for each race, which suggests that differences in measured IQ scores map onto differences in life outcomes. To the extent that a medical condition makes someone test poorly, it generally also makes them live poorly. (There are a handful of prominent exceptions to this- like dyslexia- which don’t significantly impact the main point.)
Now, where those IQ differences come from in the first place is an interesting question. Many people have looked at it, and the consensus answer for individual IQ differences is “somewhere between 50% and 80% of it is genetic,” and the extrapolation from that to group IQ differences is somewhat controversial but seems straightforward to me. A perhaps more interesting question is “what knobs do we have to adjust those IQ differences?”
However, it’s hard to believe it exists without a citation. Do you have one?
Here’s Jason Richwine explaining that all serious scientists have agreed on the basics of IQ for decades, and the media is completely mistaken on the state of reality and scientific consensus.
I still think the number is 25%, however I do not view this as a key point in our disagreement, so I will leave it at that.
It seems pretty relevant to me, because it looks like basic statistical innumeracy on your part, unless you think the IQ distribution of African Americans is tremendously skewed such that the mean intelligence is the 75th percentile of intelligence, rather than the 50th percentile like it would be in a symmetric distribution. (Or you think that the African average is higher than the African American average, which is very much not the case.)
That’s a saying? Are there also sayings “Life is a test of height.”, “Life is a test of immune system efficiency” and “Life is a test of facial symmetry”? We may as well round out the set. Anything of comparable test significance that I missed? Oh! “Life is a test of breast perkiness” and “Life is a test of capacity for situation-appropriate violence.”
(I actually agree with the point of the rest of the paragraph.)
Are there also sayings “Life is a test of height.”, “Life is a test of immune system efficiency” and “Life is a test of facial symmetry”? We may as well round out the set.
Those may be qualitatively similar but I would suggest they are quantitatively different. I would be surprised if facial symmetry did not correlate with income, health, social status, and so on, but I would expect the correlation to be much lower than the correlation with IQ. The saying means that most metrics of life success are moderately highly g-loaded, and so it makes sense that IQ correlates positively with basically everything good.
Those may be qualitatively similar but I would suggest they are quantitatively different.
I think you either drastically overestimate the impact of IQ or underestimate the predictive value of those other factors of life success—particularly in environments different to those experienced by the white male nerd class of first world countries. Regardless, the paragraph with that alleged saying redacted would be far more persuasive than the one with it included. It strongly undermines the credibility of your point. I currently agree with you despite the opening sentence, not because of it.
I think you either drastically overestimate the impact of IQ or underestimate the predictive value of those other factors of life success
Perhaps we should switch to numbers to make it easier to communicate. I haven’t looked at any numbers recently, so I don’t expect these guesses to be particularly accurate, but I’d guess IQ correlates .2 to .6 with most interesting measures of life success, and height correlates around 0 to 0.1 (after controlling for IQ). I’d guess facial symmetry has correlation >0.3 with other health-related things, a correlation around 0.4 with social things, and a correlation below 0.3 with the rest.
If you have a source handy that estimates these sorts of correlations, I’d like to see it, but I don’t think it’s important enough to spend time hunting something down.
I would be very surprised if IQ correlates at .6 with, say, wealth or income. Parental wealth and income possibly correlate no more than 0.5 to childrens’ incomes, and it would be frankly remarkable for IQ to be (1) transmitted intergenerationally to a large degree, and (2) more closely correlated to financial outcomes than one’s parent’s financial outcomes, since your parents often give you not only your genes, but your inheritance/early support, financial assumptions, and first set of career contacts.
Intelligence: Knowns and Unknowns claims that parental SES and IQ are correlated at .33; that parental SES explains one third of social status variance (which implies r=.58) and one fifth of income variance (r=.45); that IQ explains about a quarter of the social status variance (r=.5) and a sixth of the income variance (r=.4), and that also correcting for parental SES reduces the predictive ability of IQ by a quarter. I would expect more recent numbers to be broadly similar.
Thanks for the link. It’s a nice summary of the state of research a few years back, and anybody who’s interested in the topic should read it.
It is probably even more interesting to me because it tacks pretty hard away from the conclusions some people have drawn in this thread. The authors clearly did not believe that the well-attested differences in IQ testing across ethnic groups could be ascribed to genetic factors.
The authors clearly did not believe that the well-attested differences in IQ testing across ethnic groups could be ascribed to genetic factors.
I think that there’s not definitive evidence on the subject, even today. The definitive evidence would be if we knew the specifics of the causal link between genetics and IQ and had representative genetic samples from different racial groups, so we could look at the prevalence of various IQ genes and calculate what we’d estimate the average racial IQ to be for various groups from their genes. That’d give us an estimate of the genetic factors, and the difference between that and measured IQ would give us an estimate of the environmental factors.
My read of the field, though, is that the majority of the evidence points to the majority of the difference between racial groups being explained by genetic factors, and the trend has been that the hereditarian position has been growing more solid over time, especially as more and more people have been sequenced.
For example, African Americans represent a significant observational data source on ancestry and intelligence, since while the average African American has 80% African ancestry, that percentage can vary significantly from person to person. Intelligence: Knowns and Unknowns reports that a study that used blood groups to determine ancestry failed to find a correlation between European ancestry and IQ; more recent research claims to have found a correlation between European ancestry and IQ and controlled for the impact of skin color.
I haven’t looked at any numbers recently, so I don’t expect these guesses to be particularly accurate, but I’d guess IQ correlates .2 to .6 with most interesting measures of life success, and height correlates around 0 to 0.1 (after controlling for IQ).
Do you similarly control the IQ finding for height? For obvious reasons that is necessary for consistency.
I’d certainly expect (based on loose memories of studies encountered) height to predict more than ‘0 to 0.1’ and IQ to predict a heck of a lot less than 0.6, especially when considering populations that are not limited to first world nations. I wish it were otherwise, naturally. I’d love the world to be more biased in favour of my own highest stat.
In any case, I would consider it legitimate to readers who encounter “Life is an IQ test” delivered in response to the quoted context to be sufficient evidence that the comment is not worth reading and downvoting and ignoring it. It was only because I was more patient that normal that I bothered to read further and found you had a good point hidden in the detail. Do with that information what you will.
I’d love the world to be more biased in favour of my own highest stat
You can re-allocate some of that to Charisma if you work really hard (stand-up comedy is a learned skill) and if you have a British or Australian accent you get +1 just by coming to North America and talking. Provided you haven’t already maxed it, Strength is highly trainable, as are Dexterity and Constitution. Even HP, up till about 30 when bone density stops accumulating. Wisdom is extremely trainable, and there’s some evidence the world’s biased that direction, so I’d throw points there when in doubt.
Provided you haven’t already maxed it, Strength is highly trainable
In fact, even those who have reached their maximum strength potential can increase it by using the highly potent Potion of Potential Strength.
Even HP, up till about 30 when bone density stops accumulating.
HPs are primarily determined by Constitution (somewhat trainable) but in many worlds (including the real one) there is also a bonus from Strength stat. Better developed muscles are useful for absorbing damage non-critically.
Perhaps the most important stat is actually Willpower, which is also somewhat trainable and can be buffed with items and hired allies.
You can re-allocate some of that to Charisma if you work really hard (stand-up comedy is a learned skill) and if you have a British or Australian accent you get +1 just by coming to North America and talking.
Well spotted on the ‘favour’ usage! Yes, I’ve noticed a bonus there (my current girlfriend is North American), presumably the accent helped.
Do you similarly control the IQ finding for height? For obvious reasons that is necessary for consistency.
If you do a linear regression with both IQ and height as inputs, this automatically separates their (linear) effects.
But I’m not sure about the general point, because IQ is an estimate of a factor and height is an estimate of a single variable. My impression is that when you are looking for the individual effect of a component of a hidden factor, then you want to control for the factor before measuring the effect of the component, but when measuring the effect of the hidden factor you don’t control for the components. But height isn’t a component of the IQ calculation, though it does appear to be weakly related to intelligence.
I’d certainly expect (based on loose memories of studies encountered) height to predict more than ‘0 to 0.1’ and IQ to predict a heck of a lot less than 0.6, especially when considering populations that are not limited to first world nations.
I’m also having trouble remembering if the 0.05 number I remembered was an r or r^2, which would significantly impact the range. I’m finding rs of about .2 for the correlation between height and intelligence, and rs of about .2 for the correlation between height and income without controlling for intelligence. Haven’t found anything yet that does control for it. (IQ correlation with income, as mentioned in a cousin comment, is about .4.)
In any case, I would consider it legitimate to readers who encounter “Life is an IQ test” delivered in response to the quoted context to be sufficient evidence that the comment is not worth reading and downvoting and ignoring it.
It’s still not clear to me what about the saying you find objectionable. The best guess I have is that you took it to mean that the g-loading of life success was comparable to Raven’s, when I meant that they were g-loaded at all. The heart of that paragraph:
To the extent that a medical condition makes someone test poorly, it generally also makes them live poorly.
seems to me like a fair explanation of the saying, and why it’s confused to think about nurture factors influencing intelligence as separate from actual intelligence.
As a stand-alone statement, I would probably leave this alone. But as a response to “What about nurture”, the first thing that comes to mind is:
Has Vaniver adequately corrected for the just world fallacy?
The predictive ability of IQ on income (and most other statistics of interest) is very similar for each race, which suggests that differences in measured IQ scores map onto differences in life outcomes.
Ok, that’s interesting, but it does nothing to rule out nurture factors that would impact both IQ and income.
Many people have looked at it, and the consensus answer for individual IQ differences is “somewhere between 50% and 80% of it is genetic”
I agree that IQ is mostly genetic and that IQ does seem to correlate with a lot of factors. I’m not saying IQ does not exist. What I am saying is that, specifically when it comes to black people, there are other factors that are definitely influencing performance and IQ scores. Therefore I reject claims about IQ and race that haven’t controlled for known factors.
Here’s Jason Richwine explaining that all serious scientists have agreed on the basics of IQ for decades
Actually, when I read that section (it starts with “What scholars”), I parsed it like this:
Jason explicitly says that there’s a scientific consensus on many issues that seem controversial to journalists.
Jason states that virtually all psychologists (not scientists) believe there is a general mental ability factor (That he’s not saying is specifically connected to race).
Then, without qualifying these statements with anything along the lines of “most x believe”, he states: “In terms of group differences, people of northeast Asian descent have higher average IQ scores than people of European lineage, who in turn have higher average scores than people of sub-Saharan African descent.”
I will not assume that this sequence of claims means that the group differences statement is also something scientists have a consensus about. If I did, that would be a non-sequitur.
Also, below that, he writes:
“It is possible that genetic factors could influence IQ differences among ethnic groups, but many scientists are withholding judgment until DNA studies are able to link specific gene combinations with IQ.”
This is where I stop reading the article because it is clear to me that it does not say “there’s a scientific consensus that there’s a link between race and IQ”. If you have a credible source for that claim, I’ll be curious about it. No more Politico articles please.
It seems pretty relevant to me
It might or might not have been an error. In any case, I’m not going to go digging for that right now because I still think knowing the percentage is irrelevant to the current point. Whether the figure is 50% or 25%, it is still true that a significant proportion of people will have an IQ above average and therefore it would be hasty generalization to assume that a person of a certain group was an idiot. That is one way in which the exact number is irrelevant. However, that point about hasty generalization is much more irrelevant at this particular moment because we haven’t even decided on a prior, let alone have we got a decent posterior—so the step where we have a concern about making a hasty generalization based on our probabilities should be in this disagreement’s future. If it becomes relevant, I will dig around, but not right now.
Ok, that’s interesting, but it does nothing to rule out nurture factors that would impact both IQ and income.
It’s not clear to me why you would be interested in nurture factors. There are two things going on here: the ability of IQ to measure intelligence, and the historical causes of intelligence.
With the exception of disorders that prevent people from testing well without significantly impacting life outcomes, the historical causes of intelligence don’t appear to have much to do with the ability of IQ to measure intelligence. A nurture factor (like, for example, being breastfed as a child or being struck on the head) actually alters someone’s intelligence, and their intelligence influences both their test scores and their income.
What I am saying is that, specifically when it comes to black people, there are other factors that are definitely influencing performance and IQ scores. Therefore I reject claims about IQ and race that haven’t controlled for known factors.
Again, this looks like it’s mixing up the historical causes and the predictive ability. If the predictive ability is the same independent of race (it is), then it doesn’t matter why the racial IQ averages are the way they are. What we would need to show to discount IQ measurements is that the IQ measurements are not as predictive for members of one race than another.
As an example of a real bias like this, girls tend to get better grades than standardized test scores alone would predict. In order to get an accurate estimate of what a girl’s grades would be from her standardized test scores, you need to adjust upwards because she’s a girl. Symmetrically, boys score better than one would expect from their grades, and so when predicting scores one needs to adjust upwards. When moving in the opposite direction, one would need to adjust downwards; a girl’s grades overestimate her standardized test scores. But note that this doesn’t mean we throw out the data- it’s still predictive! We just adjust it the correct quantitative amount.
Now, do we know the historical causes of that effect? I’m not familiar with that field, but it seems like there are lots of plausible theories that probably have support. Even without knowing the causes, though, we can use our estimates of the size of the effect in order to predict more accurately.
virtually all psychologists (not scientists)
What would you call a scientist who studies intelligence? (I suppose I should also make clear that by “serious” I mean a scientist speaking confidently in their field of expertise.)
Then, without qualifying these statements with anything along the lines of “most x believe”, he states
One does not say “most scientists believe that hydrogen has one proton,” one says “hydrogen has one proton.”
If you have a credible source for that claim, I’ll be curious about it. No more Politico articles please.
Here’s the APA report he references. The group means section starts on page 16.
In general, though, asking for citations like this is really frustrating, because it doesn’t seem like the true rejection. The linked Richwine article referenced more serious sources that you could find if interested, and even if you didn’t notice that Googling “racial IQ averages” leads to this as the fourth hit, and if sufficiently motivated you could find the paper that journalist was writing about, and so on.
But if you’re not curious enough to seek out this information, and you don’t seem to have updated on the other information I’ve provided, what reason do I have to expect that the difference between my position and your position is that I have citations, and as soon as I share them you’ll adopt my position?
Whether the figure is 50% or 25%, it is still true that a significant proportion of people will have an IQ above average and therefore it would be hasty generalization to assume that a person of a certain group was an idiot.
Sure. When you think in distributions, an estimate generally comes with both a mode and a precision (or, relatedly, the standard deviation). Knowing someone is African American gives you an estimate with a mode of 85 and standard deviation of 15, which has a non-trivial but small chance of being over 120. Knowing someone got a 120 on a recent IQ test gives you an estimate with a mode slightly south of 120 and a standard deviation of probably 2-5, depending on the precision of the test.
As the saying goes, “Life is an IQ test.” The predictive ability of IQ on income (and most other statistics of interest) is very similar for each race, which suggests that differences in measured IQ scores map onto differences in life outcomes. To the extent that a medical condition makes someone test poorly, it generally also makes them live poorly. (There are a handful of prominent exceptions to this- like dyslexia- which don’t significantly impact the main point.)
Now, where those IQ differences come from in the first place is an interesting question. Many people have looked at it, and the consensus answer for individual IQ differences is “somewhere between 50% and 80% of it is genetic,” and the extrapolation from that to group IQ differences is somewhat controversial but seems straightforward to me. A perhaps more interesting question is “what knobs do we have to adjust those IQ differences?”
Here’s Jason Richwine explaining that all serious scientists have agreed on the basics of IQ for decades, and the media is completely mistaken on the state of reality and scientific consensus.
It seems pretty relevant to me, because it looks like basic statistical innumeracy on your part, unless you think the IQ distribution of African Americans is tremendously skewed such that the mean intelligence is the 75th percentile of intelligence, rather than the 50th percentile like it would be in a symmetric distribution. (Or you think that the African average is higher than the African American average, which is very much not the case.)
That’s a saying? Are there also sayings “Life is a test of height.”, “Life is a test of immune system efficiency” and “Life is a test of facial symmetry”? We may as well round out the set. Anything of comparable test significance that I missed? Oh! “Life is a test of breast perkiness” and “Life is a test of capacity for situation-appropriate violence.”
(I actually agree with the point of the rest of the paragraph.)
EDIT: sorry, misunderstood your comment.
Those may be qualitatively similar but I would suggest they are quantitatively different. I would be surprised if facial symmetry did not correlate with income, health, social status, and so on, but I would expect the correlation to be much lower than the correlation with IQ. The saying means that most metrics of life success are moderately highly g-loaded, and so it makes sense that IQ correlates positively with basically everything good.
I think you either drastically overestimate the impact of IQ or underestimate the predictive value of those other factors of life success—particularly in environments different to those experienced by the white male nerd class of first world countries. Regardless, the paragraph with that alleged saying redacted would be far more persuasive than the one with it included. It strongly undermines the credibility of your point. I currently agree with you despite the opening sentence, not because of it.
Perhaps we should switch to numbers to make it easier to communicate. I haven’t looked at any numbers recently, so I don’t expect these guesses to be particularly accurate, but I’d guess IQ correlates .2 to .6 with most interesting measures of life success, and height correlates around 0 to 0.1 (after controlling for IQ). I’d guess facial symmetry has correlation >0.3 with other health-related things, a correlation around 0.4 with social things, and a correlation below 0.3 with the rest.
If you have a source handy that estimates these sorts of correlations, I’d like to see it, but I don’t think it’s important enough to spend time hunting something down.
I would be very surprised if IQ correlates at .6 with, say, wealth or income. Parental wealth and income possibly correlate no more than 0.5 to childrens’ incomes, and it would be frankly remarkable for IQ to be (1) transmitted intergenerationally to a large degree, and (2) more closely correlated to financial outcomes than one’s parent’s financial outcomes, since your parents often give you not only your genes, but your inheritance/early support, financial assumptions, and first set of career contacts.
Intelligence: Knowns and Unknowns claims that parental SES and IQ are correlated at .33; that parental SES explains one third of social status variance (which implies r=.58) and one fifth of income variance (r=.45); that IQ explains about a quarter of the social status variance (r=.5) and a sixth of the income variance (r=.4), and that also correcting for parental SES reduces the predictive ability of IQ by a quarter. I would expect more recent numbers to be broadly similar.
Thanks for the link. It’s a nice summary of the state of research a few years back, and anybody who’s interested in the topic should read it.
It is probably even more interesting to me because it tacks pretty hard away from the conclusions some people have drawn in this thread. The authors clearly did not believe that the well-attested differences in IQ testing across ethnic groups could be ascribed to genetic factors.
You’re welcome!
I think that there’s not definitive evidence on the subject, even today. The definitive evidence would be if we knew the specifics of the causal link between genetics and IQ and had representative genetic samples from different racial groups, so we could look at the prevalence of various IQ genes and calculate what we’d estimate the average racial IQ to be for various groups from their genes. That’d give us an estimate of the genetic factors, and the difference between that and measured IQ would give us an estimate of the environmental factors.
My read of the field, though, is that the majority of the evidence points to the majority of the difference between racial groups being explained by genetic factors, and the trend has been that the hereditarian position has been growing more solid over time, especially as more and more people have been sequenced.
For example, African Americans represent a significant observational data source on ancestry and intelligence, since while the average African American has 80% African ancestry, that percentage can vary significantly from person to person. Intelligence: Knowns and Unknowns reports that a study that used blood groups to determine ancestry failed to find a correlation between European ancestry and IQ; more recent research claims to have found a correlation between European ancestry and IQ and controlled for the impact of skin color.
Do you similarly control the IQ finding for height? For obvious reasons that is necessary for consistency.
I’d certainly expect (based on loose memories of studies encountered) height to predict more than ‘0 to 0.1’ and IQ to predict a heck of a lot less than 0.6, especially when considering populations that are not limited to first world nations. I wish it were otherwise, naturally. I’d love the world to be more biased in favour of my own highest stat.
In any case, I would consider it legitimate to readers who encounter “Life is an IQ test” delivered in response to the quoted context to be sufficient evidence that the comment is not worth reading and downvoting and ignoring it. It was only because I was more patient that normal that I bothered to read further and found you had a good point hidden in the detail. Do with that information what you will.
You can re-allocate some of that to Charisma if you work really hard (stand-up comedy is a learned skill) and if you have a British or Australian accent you get +1 just by coming to North America and talking. Provided you haven’t already maxed it, Strength is highly trainable, as are Dexterity and Constitution. Even HP, up till about 30 when bone density stops accumulating. Wisdom is extremely trainable, and there’s some evidence the world’s biased that direction, so I’d throw points there when in doubt.
In fact, even those who have reached their maximum strength potential can increase it by using the highly potent Potion of Potential Strength.
HPs are primarily determined by Constitution (somewhat trainable) but in many worlds (including the real one) there is also a bonus from Strength stat. Better developed muscles are useful for absorbing damage non-critically.
Perhaps the most important stat is actually Willpower, which is also somewhat trainable and can be buffed with items and hired allies.
Well spotted on the ‘favour’ usage! Yes, I’ve noticed a bonus there (my current girlfriend is North American), presumably the accent helped.
If you do a linear regression with both IQ and height as inputs, this automatically separates their (linear) effects.
But I’m not sure about the general point, because IQ is an estimate of a factor and height is an estimate of a single variable. My impression is that when you are looking for the individual effect of a component of a hidden factor, then you want to control for the factor before measuring the effect of the component, but when measuring the effect of the hidden factor you don’t control for the components. But height isn’t a component of the IQ calculation, though it does appear to be weakly related to intelligence.
I’m also having trouble remembering if the 0.05 number I remembered was an r or r^2, which would significantly impact the range. I’m finding rs of about .2 for the correlation between height and intelligence, and rs of about .2 for the correlation between height and income without controlling for intelligence. Haven’t found anything yet that does control for it. (IQ correlation with income, as mentioned in a cousin comment, is about .4.)
It’s still not clear to me what about the saying you find objectionable. The best guess I have is that you took it to mean that the g-loading of life success was comparable to Raven’s, when I meant that they were g-loaded at all. The heart of that paragraph:
seems to me like a fair explanation of the saying, and why it’s confused to think about nurture factors influencing intelligence as separate from actual intelligence.
As a stand-alone statement, I would probably leave this alone. But as a response to “What about nurture”, the first thing that comes to mind is:
Has Vaniver adequately corrected for the just world fallacy?
Ok, that’s interesting, but it does nothing to rule out nurture factors that would impact both IQ and income.
I agree that IQ is mostly genetic and that IQ does seem to correlate with a lot of factors. I’m not saying IQ does not exist. What I am saying is that, specifically when it comes to black people, there are other factors that are definitely influencing performance and IQ scores. Therefore I reject claims about IQ and race that haven’t controlled for known factors.
Actually, when I read that section (it starts with “What scholars”), I parsed it like this:
Jason explicitly says that there’s a scientific consensus on many issues that seem controversial to journalists.
Jason states that virtually all psychologists (not scientists) believe there is a general mental ability factor (That he’s not saying is specifically connected to race).
Then, without qualifying these statements with anything along the lines of “most x believe”, he states: “In terms of group differences, people of northeast Asian descent have higher average IQ scores than people of European lineage, who in turn have higher average scores than people of sub-Saharan African descent.”
I will not assume that this sequence of claims means that the group differences statement is also something scientists have a consensus about. If I did, that would be a non-sequitur.
Also, below that, he writes:
“It is possible that genetic factors could influence IQ differences among ethnic groups, but many scientists are withholding judgment until DNA studies are able to link specific gene combinations with IQ.”
This is where I stop reading the article because it is clear to me that it does not say “there’s a scientific consensus that there’s a link between race and IQ”. If you have a credible source for that claim, I’ll be curious about it. No more Politico articles please.
It might or might not have been an error. In any case, I’m not going to go digging for that right now because I still think knowing the percentage is irrelevant to the current point. Whether the figure is 50% or 25%, it is still true that a significant proportion of people will have an IQ above average and therefore it would be hasty generalization to assume that a person of a certain group was an idiot. That is one way in which the exact number is irrelevant. However, that point about hasty generalization is much more irrelevant at this particular moment because we haven’t even decided on a prior, let alone have we got a decent posterior—so the step where we have a concern about making a hasty generalization based on our probabilities should be in this disagreement’s future. If it becomes relevant, I will dig around, but not right now.
It’s not clear to me why you would be interested in nurture factors. There are two things going on here: the ability of IQ to measure intelligence, and the historical causes of intelligence.
With the exception of disorders that prevent people from testing well without significantly impacting life outcomes, the historical causes of intelligence don’t appear to have much to do with the ability of IQ to measure intelligence. A nurture factor (like, for example, being breastfed as a child or being struck on the head) actually alters someone’s intelligence, and their intelligence influences both their test scores and their income.
Again, this looks like it’s mixing up the historical causes and the predictive ability. If the predictive ability is the same independent of race (it is), then it doesn’t matter why the racial IQ averages are the way they are. What we would need to show to discount IQ measurements is that the IQ measurements are not as predictive for members of one race than another.
As an example of a real bias like this, girls tend to get better grades than standardized test scores alone would predict. In order to get an accurate estimate of what a girl’s grades would be from her standardized test scores, you need to adjust upwards because she’s a girl. Symmetrically, boys score better than one would expect from their grades, and so when predicting scores one needs to adjust upwards. When moving in the opposite direction, one would need to adjust downwards; a girl’s grades overestimate her standardized test scores. But note that this doesn’t mean we throw out the data- it’s still predictive! We just adjust it the correct quantitative amount.
Now, do we know the historical causes of that effect? I’m not familiar with that field, but it seems like there are lots of plausible theories that probably have support. Even without knowing the causes, though, we can use our estimates of the size of the effect in order to predict more accurately.
What would you call a scientist who studies intelligence? (I suppose I should also make clear that by “serious” I mean a scientist speaking confidently in their field of expertise.)
One does not say “most scientists believe that hydrogen has one proton,” one says “hydrogen has one proton.”
Here’s the APA report he references. The group means section starts on page 16.
In general, though, asking for citations like this is really frustrating, because it doesn’t seem like the true rejection. The linked Richwine article referenced more serious sources that you could find if interested, and even if you didn’t notice that Googling “racial IQ averages” leads to this as the fourth hit, and if sufficiently motivated you could find the paper that journalist was writing about, and so on.
But if you’re not curious enough to seek out this information, and you don’t seem to have updated on the other information I’ve provided, what reason do I have to expect that the difference between my position and your position is that I have citations, and as soon as I share them you’ll adopt my position?
Sure. When you think in distributions, an estimate generally comes with both a mode and a precision (or, relatedly, the standard deviation). Knowing someone is African American gives you an estimate with a mode of 85 and standard deviation of 15, which has a non-trivial but small chance of being over 120. Knowing someone got a 120 on a recent IQ test gives you an estimate with a mode slightly south of 120 and a standard deviation of probably 2-5, depending on the precision of the test.