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Heritable general intelligence

By now you will know that I have often been sceptical about the view that we are becoming less intelligent. Estimating these matters is problematical. For example, can we judge where Stephen Hawkings will stand in the canon of theoretical physicists? I think it would be premature to judge, particularly when at the moment we do not have ways of testing his conjectures. Giving it 50 years seems prudent. Something may turn up. Indeed, I think Charles Murray was absolutely right, in describing human accomplishment, to stop the clock 50 years back. We are too bound up by present enthusiasms. For example, the movie we saw last week comes to mind easily, whereas only the best of those watched a decade ago stand out in memory.

However, one should not permanently discard a hypothesis simply because the early work did not support it. The potential problem was first noted by Galton in 1869. In the 1930s Raymond Cattell was pretty sure that the greater fertility of poorer and duller couples was going to bring down the population average, but was surprised to find that the data showed a contrary trend. Perhaps this was because the effects of copious fertilizer overcame a drop in the quality of the seed, but results are results, and the dysgenic hypothesis looked weak. Of course, to continue the agricultural analogy, yields could also be adversely affected by over-use of pesticides. One possible cause of less capable brains is that these sensitive organs are being poisoned by man-made toxins.

All this and more is covered in the introduction to a new paper:

What Caused over a Century of Decline in General Intelligence? Testing Predictions from the Genetic Selection and Neurotoxin Hypotheses Michael A. Woodley of Menie & Matthew A. Sarraf & Mateo Peñaherrera-Aguirre & Heitor B. F. Fernandes & David Becker

https://drive.google.com/file/d/1G85ClSUjG8CiypqXtNxofaEObSI-M2OW/view?usp=sharing

What are we to make of all this? The Woodley et al. argument is that general intelligence, the important and heritable part of mental ability, is falling; and that specific skills, the environmentally-influenced non-heritable part of mental ability, had risen over the last century and is now on a plateau.

The supportive findings are as follows: if you take the g loadings of mental tests (their saturation on the general factor of intelligence) and you link those loadings with the effect sizes of things like inbreeding depression and correlations with motor reaction times, then the strength of selection against intelligence (duller citizens having larger families) is more pronounced on g loaded abilities, but correlates negatively with the Flynn Effect (the secular rise in many, but not all mental tests).

So, it is better to track general ability rather than specific specialised skills.

If you look at the loadings for g over the decades of the last century you will see that the presumed dysgenic effect is not uniform and consistent, as would be expected from a gentle but persistent decline. The authors are aware of this, and provide counter-arguments, but it remains a puzzle, and in my view weakens the hypothesis somewhat.

heritable gen intell by decades

Overall, we have a strong and coherent case for the dysgenic hypothesis, which critics can now respond to.

 
• Category: Science • Tags: Dysgenic 
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  1. nickels says:

    Genetic decay is across the board.
    This is why the Greeks had such a complex and beautiful language, and such a rich culture of art, architecture and philosophy.
    Today’s people are a truly sad lot.

    Read More
    • Replies: @RaceRealist88
    Just-so stories.
    ReplyAgree/Disagree/Etc.
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  2. dearieme says:

    It’s not a good idea to have an enstupiding population facing – I guess – a Little Ice Age.

    Read More
    • Replies: @TWS
    Absolutely best time to face hard times. We need to break out of this, 'mouse utopia' and face a bit of hardship while we still have some of the gains we made in the last thousands years.
    , @Pyrrhus
    Or any Age, for that matter...Worse yet, as I have been pointing out for years, the steady decline of scores on the SAT, the premier test in the US, despite the weakening of the test, indicates that specialized skills in math and English have also been declining. Happy talk about the Flynn Effect, which is a product of the eyestrain producing Raven Matrix test, doesn't change anything..
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  3. TWS says:
    @dearieme
    It's not a good idea to have an enstupiding population facing - I guess - a Little Ice Age.

    Absolutely best time to face hard times. We need to break out of this, ‘mouse utopia’ and face a bit of hardship while we still have some of the gains we made in the last thousands years.

    Read More
    • Replies: @Realist
    Cull the stock.
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  4. Realist says:
    @TWS
    Absolutely best time to face hard times. We need to break out of this, 'mouse utopia' and face a bit of hardship while we still have some of the gains we made in the last thousands years.

    Cull the stock.

    Read More
    • Replies: @Santoculto
    Start from you...
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  5. @Realist
    Cull the stock.

    Start from you…

    Read More
    • Replies: @Realist
    Ummm, I don't think so. From reading your comments you are a much better candidate.
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  6. Realist says:
    @Santoculto
    Start from you...

    Ummm, I don’t think so. From reading your comments you are a much better candidate.

    Read More
    • Agree: RaceRealist88
    • Replies: @Santoculto
    Why*

    Those who have stupid babies are people as you white tra$$h
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  7. Sean says:

    Daniel Dennett talks about Gregorian (Richard Gregory) creatures using mind-tools (words) from the cultural environment Maybe the brute IQ is going down but the brain power is going to certain abilities required to successfully use cultural mind-tools. . The memes are getting more sucsuccessful as we get less clever in certain ways ?

    Read More
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  8. This should not be a surprise.

    In the mid-20th century, across most of the West, governments implemented policies to attempt to prevent one of the natural consequences of increased prosperity – a consequence that works against the desire of the political class to expand the size of the herd that furnishes their source of income and wealth.

    The consequence of prosperity that they are/were concerned about is a reduction in fertility rates. That’s not because women become less fertile as societies become wealthier; it’s because they have far better things to do with their time than spend their adult lives pregnant or nursing.

    This empirical regularity has been understood for a century – it was, after all, part of the dysgenic’s analytical framework as far back as the late 19th century: the dummies reproduce in larger numbers, from a larger base, than the smarties… and so will eventually dumb-down the population by force of numbers.

    The early-to-mid 20th century saw the near-elimination of infant mortality – from 1-in-5 births in the West (and 1-in-4 in the ‘poor’ West) at the turn of the 20th century, to 0.2-in-100 by the end of the century. (Note: this is unambiguously a good thing – unlike the US Death machine, I don’t thrive on the production of dead babies).

    What didn’t happen thereafter, was a change in reproductive strategies in the bottom 50% of the income distribution; those folks kept reproducing, and the drop in infant mortality caused them to go from breeding at slightly-above-replacement, to breeding at rates several times that of the top 50% (whose strategies changed in such a way as to ensure reproduction below-replacement).

    Meanwhile, the demographic that provides 100% of the cognitive ‘grunt’ of society – the top 5-10% of the IQ distribution) was breeding well-below-replacement.

    This is why we started to see behaviours previously indicative of the ‘submerged tenth’, all the way up to the first quartile (and later, above).

    In the 1960s, women in the bottom half started to control their reproduction more assiduously (with the birth control pill) and population growth in the West stalled. (Note: by ‘population growth’ here, I mean ‘natural increase’ – i.e., excluding inward-migration and the first-generation of children born to immigrants, who breed faster than the incumbents).

    So governments were – and are – staring down a ‘funding barrel’: they had made promises to workers (pensions and aged health-care) to prevent workers from agitating for a ‘fairer’ share of additional productivity… and if the population is growing more slowly than the stock of living retirees, that scheme goes through zero rapidly. (Yes: government pensions are a Ponzi scheme – unambiguously).

    So what did they do? They incentivised reproduction (the most flagrant example of this is the Australian ‘baby bonus’, but ‘child benefit’ and ‘child tax credit’ and ‘family allowance’ and other such incentives are the same thing).

    And here’s where it gets slightly technical.

    The quantum involved in these subsidies-to-reproduction, were not large enough to induce high-IQ women to devote their scarce time to reproduction. Like all subsidies, they had their greatest impact on people with a high marginal utility of money… i.e., the poor.

    Add to this that the poor (and particularly poor women) are spectacularly bad at estimating the costs of future things (e.g., the cost of raising an infant), and have very high discount rates (e.g., they will take out loans that have 50% and higher interest rates).

    What this meant was that the ‘reproductive subsidies’ were effectively ‘subsidies to Delta-production‘ (using Huxley’s taxonomy) – which reintroduced and amplified the disproportionate growth of the bottom fifth of the IQ distribution (and again, we see things that were previously only observed below the bottom decile, right up to the fourth quartile).

    The political class is indifferent to this outcome, because so far it’s been working: the top 5-10% of the IQ distribution continues to generate advances in productivity that are primarily driven by the characteristics of capital goods, with progressively lower cognitive requirements for labour. This has generated enough operating surplus for the political class to continue to build palaces for themselves out of taxation.

    But it now seems that the gains from this strategy are starting to peter out; firstly, once labour becomes almost irrelevant to production, there will be a large underclass who is economically useless and will agitate for, e.g., Universal Basic Income; secondly, those who generate the innovations are getting sick of seeing the benefits of their innovation being transferred to government and its cronies, and are looking for ways to get out of the tax livestock herd.

    Prior to the mid-20th century, the predictable outcome of this would have been a large-scale land war – which would kill off ~6% of the dumb (surplus) males and slow the growth rate of the Deltas. There would be a rapid expansion in per-capita income after the war, and this would make the bottom 80% think that things were better than the status quo antebellum.

    Nowadays large-scale land war is not an option, since the technology of warfare is sufficiently destructive that a WWII-sized operation between peer-rivals would have a very good chance of spiralling into an existential-risk event.

    I’m not overly concerned: before my hundredth birthday (2065), those who want to will be able to virtualise (de-meatbag their personality), slip the surly bonds of Earth and dance through space on laughter-silvered wings. So there’s that.

    Read More
    • Replies: @Mishra
    That was a really thoughtful and comprehensive analysis. Thanks.
    , @Johan Meyer
    Yet in the US, since the early 90s, teen pregnancy has been dropping across the board, and it has dropped by more than half in New York since 2009 alone.

    There is an assumption, that because the scores of a given cohort of SAT/et cetera test takers are correlated with the test takers' IQs, that for a consistent test over time, there will be a consistent algebraic relationship between test scores and time. This assumption is unlikely to be correct, as the tests are culturally loaded, despite being very cognitive.

    There is a dubious binary distinction made between culturally loaded and cognitively loaded. A problem can require both, and require the combination of special knowledge and intelligence. If the likelihood of success on such a problem is a function of the product of knowledge with intellect, then the additive assumption based models will not give insight.

    Are there any studies, of the type that looks at the relationship between IQ and SAT, say, that find a consistent algebraic relationship between IQ and SAT over time? And if so, is the relationship, using individuals from multiple cohorts, homoskedastic?

    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  9. @Realist
    Ummm, I don't think so. From reading your comments you are a much better candidate.

    Why*

    Those who have stupid babies are people as you white tra$$h

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  10. To what extent is this the result of importing people of lower IQ?

    Perhaps the paper addresses the issue, so I guess I should read it.

    Read More
    • Replies: @Pyrrhus
    People of lower IQ don't take the college entrance tests, especially the SAT...And they are declining just as rapidly.
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  11. This sounds like a serious argument to just CRISPR as much of the human race as possible.

    I prefer the bio-engineering route over some kind of “traditionalist” route where we have to give up much of our personal and, perhaps, economic freedom as well.

    Read More
    • Replies: @RaceRealist88
    Implying there are 'genes for' IQ/intelligence (whatever that is), all the while IQ tests aren't construct valid. Weird...
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  12. Pyrrhus says:
    @dearieme
    It's not a good idea to have an enstupiding population facing - I guess - a Little Ice Age.

    Or any Age, for that matter…Worse yet, as I have been pointing out for years, the steady decline of scores on the SAT, the premier test in the US, despite the weakening of the test, indicates that specialized skills in math and English have also been declining. Happy talk about the Flynn Effect, which is a product of the eyestrain producing Raven Matrix test, doesn’t change anything..

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  13. Pyrrhus says:
    @Peripatetic commenter
    To what extent is this the result of importing people of lower IQ?

    Perhaps the paper addresses the issue, so I guess I should read it.

    People of lower IQ don’t take the college entrance tests, especially the SAT…And they are declining just as rapidly.

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  14. 25 states require the ACT or SAT of all their students. https://www.edweek.org/ew/section/multimedia/states-require-students-take-sat-or-act.html

    Thus one cannot easily compare each state’s pool of test takers to other states, or to other years.

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter Display All Comments
  15. Mishra says:
    @Kratoklastes
    This should not be a surprise.

    In the mid-20th century, across most of the West, governments implemented policies to attempt to prevent one of the natural consequences of increased prosperity - a consequence that works against the desire of the political class to expand the size of the herd that furnishes their source of income and wealth.

    The consequence of prosperity that they are/were concerned about is a reduction in fertility rates. That's not because women become less fertile as societies become wealthier; it's because they have far better things to do with their time than spend their adult lives pregnant or nursing.

    This empirical regularity has been understood for a century - it was, after all, part of the dysgenic's analytical framework as far back as the late 19th century: the dummies reproduce in larger numbers, from a larger base, than the smarties... and so will eventually dumb-down the population by force of numbers.

    The early-to-mid 20th century saw the near-elimination of infant mortality - from 1-in-5 births in the West (and 1-in-4 in the 'poor' West) at the turn of the 20th century, to 0.2-in-100 by the end of the century. (Note: this is unambiguously a good thing - unlike the US Death machine, I don't thrive on the production of dead babies).

    What didn't happen thereafter, was a change in reproductive strategies in the bottom 50% of the income distribution; those folks kept reproducing, and the drop in infant mortality caused them to go from breeding at slightly-above-replacement, to breeding at rates several times that of the top 50% (whose strategies changed in such a way as to ensure reproduction below-replacement).

    Meanwhile, the demographic that provides 100% of the cognitive 'grunt' of society - the top 5-10% of the IQ distribution) was breeding well-below-replacement.

    This is why we started to see behaviours previously indicative of the 'submerged tenth', all the way up to the first quartile (and later, above).

    In the 1960s, women in the bottom half started to control their reproduction more assiduously (with the birth control pill) and population growth in the West stalled. (Note: by 'population growth' here, I mean 'natural increase' - i.e., excluding inward-migration and the first-generation of children born to immigrants, who breed faster than the incumbents).

    So governments were - and are - staring down a 'funding barrel': they had made promises to workers (pensions and aged health-care) to prevent workers from agitating for a 'fairer' share of additional productivity... and if the population is growing more slowly than the stock of living retirees, that scheme goes through zero rapidly. (Yes: government pensions are a Ponzi scheme - unambiguously).

    So what did they do? They incentivised reproduction (the most flagrant example of this is the Australian 'baby bonus', but 'child benefit' and 'child tax credit' and 'family allowance' and other such incentives are the same thing).

    And here's where it gets slightly technical.

    The quantum involved in these subsidies-to-reproduction, were not large enough to induce high-IQ women to devote their scarce time to reproduction. Like all subsidies, they had their greatest impact on people with a high marginal utility of money... i.e., the poor.

    Add to this that the poor (and particularly poor women) are spectacularly bad at estimating the costs of future things (e.g., the cost of raising an infant), and have very high discount rates (e.g., they will take out loans that have 50% and higher interest rates).

    What this meant was that the 'reproductive subsidies' were effectively 'subsidies to Delta-production' (using Huxley's taxonomy) - which reintroduced and amplified the disproportionate growth of the bottom fifth of the IQ distribution (and again, we see things that were previously only observed below the bottom decile, right up to the fourth quartile).

    The political class is indifferent to this outcome, because so far it's been working: the top 5-10% of the IQ distribution continues to generate advances in productivity that are primarily driven by the characteristics of capital goods, with progressively lower cognitive requirements for labour. This has generated enough operating surplus for the political class to continue to build palaces for themselves out of taxation.

    But it now seems that the gains from this strategy are starting to peter out; firstly, once labour becomes almost irrelevant to production, there will be a large underclass who is economically useless and will agitate for, e.g., Universal Basic Income; secondly, those who generate the innovations are getting sick of seeing the benefits of their innovation being transferred to government and its cronies, and are looking for ways to get out of the tax livestock herd.

    Prior to the mid-20th century, the predictable outcome of this would have been a large-scale land war - which would kill off ~6% of the dumb (surplus) males and slow the growth rate of the Deltas. There would be a rapid expansion in per-capita income after the war, and this would make the bottom 80% think that things were better than the status quo antebellum.

    Nowadays large-scale land war is not an option, since the technology of warfare is sufficiently destructive that a WWII-sized operation between peer-rivals would have a very good chance of spiralling into an existential-risk event.

    I'm not overly concerned: before my hundredth birthday (2065), those who want to will be able to virtualise (de-meatbag their personality), slip the surly bonds of Earth and dance through space on laughter-silvered wings. So there's that.

    That was a really thoughtful and comprehensive analysis. Thanks.

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  16. dearieme says:

    “How did you go bankrupt?” Bill asked.

    “Two ways,” Mike said. “Gradually and then suddenly.”

    I suppose the “gradually” would be the gentle drift you refer to, Doc. The “suddenly” would presumably refer to population replacement.

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter Display All Comments
  17. Are IQ tests construct valid? If so, evidence? If not, how do you know they test intelligence and not learned skills and knowledge?

    Read More
    • Replies: @res
    This might be useful: Logical Fallacies Used to Dismiss the Evidence on Intelligence Testing
    http://www1.udel.edu/educ/gottfredson/reprints/2008logical-fallacies.doc
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  18. @nickels
    Genetic decay is across the board.
    This is why the Greeks had such a complex and beautiful language, and such a rich culture of art, architecture and philosophy.
    Today's people are a truly sad lot.

    https://www.youtube.com/watch?v=TFisJo_IZLU

    Just-so stories.

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  19. @Abelard Lindsey
    This sounds like a serious argument to just CRISPR as much of the human race as possible.

    I prefer the bio-engineering route over some kind of "traditionalist" route where we have to give up much of our personal and, perhaps, economic freedom as well.

    Implying there are ‘genes for’ IQ/intelligence (whatever that is), all the while IQ tests aren’t construct valid. Weird…

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  20. @Kratoklastes
    This should not be a surprise.

    In the mid-20th century, across most of the West, governments implemented policies to attempt to prevent one of the natural consequences of increased prosperity - a consequence that works against the desire of the political class to expand the size of the herd that furnishes their source of income and wealth.

    The consequence of prosperity that they are/were concerned about is a reduction in fertility rates. That's not because women become less fertile as societies become wealthier; it's because they have far better things to do with their time than spend their adult lives pregnant or nursing.

    This empirical regularity has been understood for a century - it was, after all, part of the dysgenic's analytical framework as far back as the late 19th century: the dummies reproduce in larger numbers, from a larger base, than the smarties... and so will eventually dumb-down the population by force of numbers.

    The early-to-mid 20th century saw the near-elimination of infant mortality - from 1-in-5 births in the West (and 1-in-4 in the 'poor' West) at the turn of the 20th century, to 0.2-in-100 by the end of the century. (Note: this is unambiguously a good thing - unlike the US Death machine, I don't thrive on the production of dead babies).

    What didn't happen thereafter, was a change in reproductive strategies in the bottom 50% of the income distribution; those folks kept reproducing, and the drop in infant mortality caused them to go from breeding at slightly-above-replacement, to breeding at rates several times that of the top 50% (whose strategies changed in such a way as to ensure reproduction below-replacement).

    Meanwhile, the demographic that provides 100% of the cognitive 'grunt' of society - the top 5-10% of the IQ distribution) was breeding well-below-replacement.

    This is why we started to see behaviours previously indicative of the 'submerged tenth', all the way up to the first quartile (and later, above).

    In the 1960s, women in the bottom half started to control their reproduction more assiduously (with the birth control pill) and population growth in the West stalled. (Note: by 'population growth' here, I mean 'natural increase' - i.e., excluding inward-migration and the first-generation of children born to immigrants, who breed faster than the incumbents).

    So governments were - and are - staring down a 'funding barrel': they had made promises to workers (pensions and aged health-care) to prevent workers from agitating for a 'fairer' share of additional productivity... and if the population is growing more slowly than the stock of living retirees, that scheme goes through zero rapidly. (Yes: government pensions are a Ponzi scheme - unambiguously).

    So what did they do? They incentivised reproduction (the most flagrant example of this is the Australian 'baby bonus', but 'child benefit' and 'child tax credit' and 'family allowance' and other such incentives are the same thing).

    And here's where it gets slightly technical.

    The quantum involved in these subsidies-to-reproduction, were not large enough to induce high-IQ women to devote their scarce time to reproduction. Like all subsidies, they had their greatest impact on people with a high marginal utility of money... i.e., the poor.

    Add to this that the poor (and particularly poor women) are spectacularly bad at estimating the costs of future things (e.g., the cost of raising an infant), and have very high discount rates (e.g., they will take out loans that have 50% and higher interest rates).

    What this meant was that the 'reproductive subsidies' were effectively 'subsidies to Delta-production' (using Huxley's taxonomy) - which reintroduced and amplified the disproportionate growth of the bottom fifth of the IQ distribution (and again, we see things that were previously only observed below the bottom decile, right up to the fourth quartile).

    The political class is indifferent to this outcome, because so far it's been working: the top 5-10% of the IQ distribution continues to generate advances in productivity that are primarily driven by the characteristics of capital goods, with progressively lower cognitive requirements for labour. This has generated enough operating surplus for the political class to continue to build palaces for themselves out of taxation.

    But it now seems that the gains from this strategy are starting to peter out; firstly, once labour becomes almost irrelevant to production, there will be a large underclass who is economically useless and will agitate for, e.g., Universal Basic Income; secondly, those who generate the innovations are getting sick of seeing the benefits of their innovation being transferred to government and its cronies, and are looking for ways to get out of the tax livestock herd.

    Prior to the mid-20th century, the predictable outcome of this would have been a large-scale land war - which would kill off ~6% of the dumb (surplus) males and slow the growth rate of the Deltas. There would be a rapid expansion in per-capita income after the war, and this would make the bottom 80% think that things were better than the status quo antebellum.

    Nowadays large-scale land war is not an option, since the technology of warfare is sufficiently destructive that a WWII-sized operation between peer-rivals would have a very good chance of spiralling into an existential-risk event.

    I'm not overly concerned: before my hundredth birthday (2065), those who want to will be able to virtualise (de-meatbag their personality), slip the surly bonds of Earth and dance through space on laughter-silvered wings. So there's that.

    Yet in the US, since the early 90s, teen pregnancy has been dropping across the board, and it has dropped by more than half in New York since 2009 alone.

    There is an assumption, that because the scores of a given cohort of SAT/et cetera test takers are correlated with the test takers’ IQs, that for a consistent test over time, there will be a consistent algebraic relationship between test scores and time. This assumption is unlikely to be correct, as the tests are culturally loaded, despite being very cognitive.

    There is a dubious binary distinction made between culturally loaded and cognitively loaded. A problem can require both, and require the combination of special knowledge and intelligence. If the likelihood of success on such a problem is a function of the product of knowledge with intellect, then the additive assumption based models will not give insight.

    Are there any studies, of the type that looks at the relationship between IQ and SAT, say, that find a consistent algebraic relationship between IQ and SAT over time? And if so, is the relationship, using individuals from multiple cohorts, homoskedastic?

    Read More
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  21. res says:
    @RaceRealist88
    Are IQ tests construct valid? If so, evidence? If not, how do you know they test intelligence and not learned skills and knowledge?

    This might be useful: Logical Fallacies Used to Dismiss the Evidence on Intelligence Testing

    http://www1.udel.edu/educ/gottfredson/reprints/2008logical-fallacies.doc

    Read More
    • Replies: @RaceRealist88
    I need to reread that to refresh my memory. I'll do so by this weekend. Does she bring up construct validity? If so, quote?
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  22. @res
    This might be useful: Logical Fallacies Used to Dismiss the Evidence on Intelligence Testing
    http://www1.udel.edu/educ/gottfredson/reprints/2008logical-fallacies.doc

    I need to reread that to refresh my memory. I’ll do so by this weekend. Does she bring up construct validity? If so, quote?

    Read More
    • Replies: @res
    She does, but it was unsatisfying in small quote form. Easy enough to search for it in the document. I suspect she uses a different definition of "construct validity" than you do and I am tired of those arguments.
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  23. res says:
    @RaceRealist88
    I need to reread that to refresh my memory. I'll do so by this weekend. Does she bring up construct validity? If so, quote?

    She does, but it was unsatisfying in small quote form. Easy enough to search for it in the document. I suspect she uses a different definition of “construct validity” than you do and I am tired of those arguments.

    Read More
    • Replies: @RaceRealist88
    Gottfredson provides no evidence that IQ tests are construct valid. Why are you tired of it? It should be one of the most important things to discuss regarding IQ. If the tests aren't construct valid then how do you know it tests 'intelligence', even 'a bit'?
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  24. @res
    She does, but it was unsatisfying in small quote form. Easy enough to search for it in the document. I suspect she uses a different definition of "construct validity" than you do and I am tired of those arguments.

    Gottfredson provides no evidence that IQ tests are construct valid. Why are you tired of it? It should be one of the most important things to discuss regarding IQ. If the tests aren’t construct valid then how do you know it tests ‘intelligence’, even ‘a bit’?

    Read More
    • Replies: @RaceRealist88
    Mechanistically relate differences in one variable to the other, like breath alcohol and level of alcohol consumption. This is valid because it relies on a well accepted theory, and no such theory exists for 'intelligence/IQ'.

    This is the definition I use. That's what construct validity is.
    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  25. @RaceRealist88
    Gottfredson provides no evidence that IQ tests are construct valid. Why are you tired of it? It should be one of the most important things to discuss regarding IQ. If the tests aren't construct valid then how do you know it tests 'intelligence', even 'a bit'?

    Mechanistically relate differences in one variable to the other, like breath alcohol and level of alcohol consumption. This is valid because it relies on a well accepted theory, and no such theory exists for ‘intelligence/IQ’.

    This is the definition I use. That’s what construct validity is.

    Read More
    • Replies: @Anonymous
    I must wonder why you identify as a race realist. I suppose the misnomer is consistent with the broader pattern of staggering idiocy apparent in your online activity.

    If you doubt the validity of IQ tests, you should doubt the validity of every psychometric construct, since none is more predictively valid than IQ.

    "how do you know they test intelligence and not learned skills and knowledge?"

    IQ tests do in part measure "learned skills and knowledge." That you have read and written as much on this subject as you apparently have but still don't know this is further testament to your profound lack of intelligence. What you fail to understand is that one's potential to learn and retain skills and knowledge is itself a function of an ability that is almost entirely under genetic control. The high heritability of IQ explains why, despite great efforts made in a decades-long search, there are no known reliable means by which to lastingly raise an individual's IQ relative to his peers, assuming he hasn't been starved half to death or something like that: https://www.sciencedirect.com/science/article/pii/S016028961500135X. If your environment-only nonsense were true, that probably wouldn't be the case.

    You seem to rely heavily on the work of the charlatan Ken Richardson, a Marxist hack in a long tradition of lying, politically motivated critics of intelligence testing, most prominently including Gould, Lewontin, Kamin, and Rose. Ironically enough you accuse another commenter above of indulging in just-so storytelling, and yet are too dense to realize that Richardson's whole corpus is a set of ridiculous just-so stories used to wriggle out of the obvious predictive validity of IQ at the individual, regional, state, and national levels.

    Some information concerning the validity of IQ tests. Findings from behavior genetic studies of the heritability of IQ are consistent with data on brain development over the life course, giving evidence that IQ tests do measure heritable factors related to the brain: https://www.sciencedirect.com/science/article/pii/S1878929315301043#fig0005. IQ can be predicted from a number of brain properties: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3181994/. Undeniable interspecies differences in intelligence correlate in the expected way with similar brain properties, including "the number of cortical neurons, neuron packing density, interneuronal distance and axonal conduction velocity" http://rstb.royalsocietypublishing.org/content/371/1685/20150180. The correlations, even when controlling for many potential confounders, between IQ and numerous important outcomes, such as health, income, national wealth, national innovation rate, national numbers of Nobel laureates, etc., are well established and not worth repeating. Are you enough of a dullard to think this is all one big coincidence? I'm sure that demented cretin Richardson could cook up some just-so story to make it all disappear!

    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  26. Anonymous[196] • Disclaimer says:
    @RaceRealist88
    Mechanistically relate differences in one variable to the other, like breath alcohol and level of alcohol consumption. This is valid because it relies on a well accepted theory, and no such theory exists for 'intelligence/IQ'.

    This is the definition I use. That's what construct validity is.

    I must wonder why you identify as a race realist. I suppose the misnomer is consistent with the broader pattern of staggering idiocy apparent in your online activity.

    If you doubt the validity of IQ tests, you should doubt the validity of every psychometric construct, since none is more predictively valid than IQ.

    “how do you know they test intelligence and not learned skills and knowledge?”

    IQ tests do in part measure “learned skills and knowledge.” That you have read and written as much on this subject as you apparently have but still don’t know this is further testament to your profound lack of intelligence. What you fail to understand is that one’s potential to learn and retain skills and knowledge is itself a function of an ability that is almost entirely under genetic control. The high heritability of IQ explains why, despite great efforts made in a decades-long search, there are no known reliable means by which to lastingly raise an individual’s IQ relative to his peers, assuming he hasn’t been starved half to death or something like that: https://www.sciencedirect.com/science/article/pii/S016028961500135X. If your environment-only nonsense were true, that probably wouldn’t be the case.

    You seem to rely heavily on the work of the charlatan Ken Richardson, a Marxist hack in a long tradition of lying, politically motivated critics of intelligence testing, most prominently including Gould, Lewontin, Kamin, and Rose. Ironically enough you accuse another commenter above of indulging in just-so storytelling, and yet are too dense to realize that Richardson’s whole corpus is a set of ridiculous just-so stories used to wriggle out of the obvious predictive validity of IQ at the individual, regional, state, and national levels.

    Some information concerning the validity of IQ tests. Findings from behavior genetic studies of the heritability of IQ are consistent with data on brain development over the life course, giving evidence that IQ tests do measure heritable factors related to the brain: https://www.sciencedirect.com/science/article/pii/S1878929315301043#fig0005. IQ can be predicted from a number of brain properties: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3181994/. Undeniable interspecies differences in intelligence correlate in the expected way with similar brain properties, including “the number of cortical neurons, neuron packing density, interneuronal distance and axonal conduction velocity” http://rstb.royalsocietypublishing.org/content/371/1685/20150180. The correlations, even when controlling for many potential confounders, between IQ and numerous important outcomes, such as health, income, national wealth, national innovation rate, national numbers of Nobel laureates, etc., are well established and not worth repeating. Are you enough of a dullard to think this is all one big coincidence? I’m sure that demented cretin Richardson could cook up some just-so story to make it all disappear!

    Read More
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  27. “I must wonder why you identify as a race realist.”

    Race is a biological reality.

    “I suppose the misnomer is consistent with the broader pattern of staggering idiocy apparent in your online activity.”

    No and you’re wrong.

    “If you doubt the validity of IQ tests, you should doubt the validity of every psychometric construct, since none is more predictively valid than IQ.”

    I doubt the validity of any test that’s not construct valid.

    “What you fail to understand is that one’s potential to learn and retain skills and knowledge is itself a function of an ability that is almost entirely under genetic control.”

    Source?

    “The high heritability of IQ”

    Based on?

    “If your environment-only nonsense were true, that probably wouldn’t be the case.”

    Do the interventions change social class?

    “You seem to rely heavily on the work of the charlatan Ken Richardson, a Marxist hack in a long tradition of lying, politically motivated critics of intelligence testing, most prominently including Gould, Lewontin, Kamin, and Rose. Ironically enough you accuse another commenter above of indulging in just-so storytelling, and yet are too dense to realize that Richardson’s whole corpus is a set of ridiculous just-so stories used to wriggle out of the obvious predictive validity of IQ at the individual, regional, state, and national levels.”

    Irrelevant.

    “Findings from behavior genetic studies of the heritability of IQ are consistent with data on brain development over the life course, giving evidence that IQ tests do measure heritable factors related to the brain”

    Based on assumptions and a computer model. And the twin studies the model used are flawed as well.

    “IQ can be predicted from a number of brain properties”

    P-FIT is a flawed theory. How do you know the differences in brain area don’t come down to experience? You don’t.

    “Undeniable interspecies differences in intelligence correlate in the expected way with similar brain properties, including “the number of cortical neurons, neuron packing density, interneuronal distance and axonal conduction velocity””

    Does this hold for humans, too?

    “The correlations, even when controlling for many potential confounders, between IQ and numerous important outcomes, such as health, income, national wealth, national innovation rate, national numbers of Nobel laureates, etc., are well established and not worth repeating”

    Forgone conclusion due to test construction. You can believe these tests ‘predict’ this but you’d be in error.

    “I’m sure that demented cretin Richardson could cook up some just-so story to make it all disappear!”

    What is a just-so story?

    Still waiting for evidence for construct validity.

    In your next comment leave the logical fallacies out of it. I won’t respond to them.

    Read More
    • Replies: @Anonymous
    "In your next comment leave the logical fallacies out of it."

    There are no fallacies in my response. You're one of these idiots who thinks all insults are ad hominems.

    Since your post contains no serious effort to rebut anything I said, but instead offers mere assertions, I'll be similarly lazy in replying.

    "Race is a biological reality."

    Yet you appear to want to deny nearly all the significant factors with respect to which races differ.

    "No and you’re wrong."

    How compelling.

    "Source?"

    http://journals.sagepub.com/doi/abs/10.1177/0956797613493292.

    Somehow you provide no sources in your fatuous reply, but demand that others give sources.

    "Based on?"

    The overwhelming majority of studies that have looked into this matter. If you aren't aware of those, you have no business discussing this subject.

    "Do the interventions change social class?"

    Is social class some magic source of cognitive disablement or advantage that necessarily depresses or raises IQ? Does SES give rise to IQ differences or is it the other way around, and to what degree? The relationship between SES and IQ has been studied countless times. SES obviously cannot explain all variation in IQ because there is enormous variation in IQ within SES categories. Some interventions that have been tried relieve the disadvantages associated with low SES that have been alleged to lower IQ. They still don't work. https://www1.udel.edu/educ/gottfredson/reprints/2005hereditarian-hypothesis.pdf. A major prediction of your environmentalist nonsense fails, and you can't explain why.

    "Irrelevant."

    You think this because you're dumb.

    "Based on assumptions and a computer model. And the twin studies the model used are flawed as well."

    What scientific work doesn't assume certain things? Take a philosophy of science 101 course and get back to me. You're an idiot to think you can dismiss a study simply because it uses a "computer model." Twin studies are sound. If you'd read any recent handbook on behavior genetics you'd be aware that all the halfwit objections from Richardson-types have been answered. In most cases they overestimate the significance of certain assumptions on which twin studies depend, such as the equal environments assumption, which even if false barely makes any difference: https://www.researchgate.net/publication/267158254_Demonstrating_the_validity_of_twin_research_in_criminology https://www.ncbi.nlm.nih.gov/pubmed/24267761.

    "P-FIT is a flawed theory. How do you know the differences in brain area don’t come down to experience? You don’t."

    Even if they come down to experience, IQ tests remain valid. But that is a ridiculous notion because brain development patterns align with the behavior genetic findings. As the simpleton you are, you're oblivious to how ludicrous it is to treat this all as a coincidence.

    IQ differences themselves can be completely environmentally based and IQ tests can still be valid. The fact that you don't realize this shows, again, that you're a moron. P-FIT is certainly in better scientific standing than the IQ-denialist bullshit coming out of your mouth. You're one of these tards who tries to pick holes in theories you don't like while remaining completely unaware of the absurdity of the alternative you prefer.

    "Does this hold for humans, too?"

    I guess you didn't read my post very clearly.

    "Forgone conclusion due to test construction. You can believe these tests ‘predict’ this but you’d be in error."

    This idiot "circularity" objection to IQ test construction is just laughable. Any valid test has to tap the same factors as the activities it's meant to predict performance in. This will lead to some similarity between the tests and those activities. This is not unique to IQ tests. However IQ tests are predictive of many things they seem to have nothing to do with at first glance. Performance on untimed IQ tests correlates with reaction times, for example. This can be satisfactorily explained only by invoking neurological phenotypes.

    "What is a just-so story?"

    An inadequately supported scientific explanation used to arrive at a conclusion one desires. Since you used the term yourself I would've hoped you already knew that.

    "Still waiting for evidence for construct validity."

    http://psycnet.apa.org/record/2009-11948-008. Not that it matters. You have enough Marxist garbage in your head that there is no amount of evidence you'll fail to explain away with fallacious babble.

    ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
  28. Anonymous[196] • Disclaimer says:
    @RaceRealist88
    "I must wonder why you identify as a race realist."

    Race is a biological reality.

    "I suppose the misnomer is consistent with the broader pattern of staggering idiocy apparent in your online activity."

    No and you're wrong.

    "If you doubt the validity of IQ tests, you should doubt the validity of every psychometric construct, since none is more predictively valid than IQ."

    I doubt the validity of any test that's not construct valid.

    "What you fail to understand is that one’s potential to learn and retain skills and knowledge is itself a function of an ability that is almost entirely under genetic control."

    Source?

    "The high heritability of IQ"

    Based on?

    "If your environment-only nonsense were true, that probably wouldn’t be the case."

    Do the interventions change social class?

    "You seem to rely heavily on the work of the charlatan Ken Richardson, a Marxist hack in a long tradition of lying, politically motivated critics of intelligence testing, most prominently including Gould, Lewontin, Kamin, and Rose. Ironically enough you accuse another commenter above of indulging in just-so storytelling, and yet are too dense to realize that Richardson’s whole corpus is a set of ridiculous just-so stories used to wriggle out of the obvious predictive validity of IQ at the individual, regional, state, and national levels."

    Irrelevant.

    "Findings from behavior genetic studies of the heritability of IQ are consistent with data on brain development over the life course, giving evidence that IQ tests do measure heritable factors related to the brain"

    Based on assumptions and a computer model. And the twin studies the model used are flawed as well.

    "IQ can be predicted from a number of brain properties"

    P-FIT is a flawed theory. How do you know the differences in brain area don't come down to experience? You don't.

    "Undeniable interspecies differences in intelligence correlate in the expected way with similar brain properties, including “the number of cortical neurons, neuron packing density, interneuronal distance and axonal conduction velocity”"

    Does this hold for humans, too?

    "The correlations, even when controlling for many potential confounders, between IQ and numerous important outcomes, such as health, income, national wealth, national innovation rate, national numbers of Nobel laureates, etc., are well established and not worth repeating"

    Forgone conclusion due to test construction. You can believe these tests 'predict' this but you'd be in error.

    "I’m sure that demented cretin Richardson could cook up some just-so story to make it all disappear!"

    What is a just-so story?

    Still waiting for evidence for construct validity.

    In your next comment leave the logical fallacies out of it. I won't respond to them.

    “In your next comment leave the logical fallacies out of it.”

    There are no fallacies in my response. You’re one of these idiots who thinks all insults are ad hominems.

    Since your post contains no serious effort to rebut anything I said, but instead offers mere assertions, I’ll be similarly lazy in replying.

    “Race is a biological reality.”

    Yet you appear to want to deny nearly all the significant factors with respect to which races differ.

    “No and you’re wrong.”

    How compelling.

    “Source?”

    http://journals.sagepub.com/doi/abs/10.1177/0956797613493292.

    Somehow you provide no sources in your fatuous reply, but demand that others give sources.

    “Based on?”

    The overwhelming majority of studies that have looked into this matter. If you aren’t aware of those, you have no business discussing this subject.

    “Do the interventions change social class?”

    Is social class some magic source of cognitive disablement or advantage that necessarily depresses or raises IQ? Does SES give rise to IQ differences or is it the other way around, and to what degree? The relationship between SES and IQ has been studied countless times. SES obviously cannot explain all variation in IQ because there is enormous variation in IQ within SES categories. Some interventions that have been tried relieve the disadvantages associated with low SES that have been alleged to lower IQ. They still don’t work. https://www1.udel.edu/educ/gottfredson/reprints/2005hereditarian-hypothesis.pdf. A major prediction of your environmentalist nonsense fails, and you can’t explain why.

    “Irrelevant.”

    You think this because you’re dumb.

    “Based on assumptions and a computer model. And the twin studies the model used are flawed as well.”

    What scientific work doesn’t assume certain things? Take a philosophy of science 101 course and get back to me. You’re an idiot to think you can dismiss a study simply because it uses a “computer model.” Twin studies are sound. If you’d read any recent handbook on behavior genetics you’d be aware that all the halfwit objections from Richardson-types have been answered. In most cases they overestimate the significance of certain assumptions on which twin studies depend, such as the equal environments assumption, which even if false barely makes any difference: https://www.researchgate.net/publication/267158254_Demonstrating_the_validity_of_twin_research_in_criminology https://www.ncbi.nlm.nih.gov/pubmed/24267761.

    “P-FIT is a flawed theory. How do you know the differences in brain area don’t come down to experience? You don’t.”

    Even if they come down to experience, IQ tests remain valid. But that is a ridiculous notion because brain development patterns align with the behavior genetic findings. As the simpleton you are, you’re oblivious to how ludicrous it is to treat this all as a coincidence.

    IQ differences themselves can be completely environmentally based and IQ tests can still be valid. The fact that you don’t realize this shows, again, that you’re a moron. P-FIT is certainly in better scientific standing than the IQ-denialist bullshit coming out of your mouth. You’re one of these tards who tries to pick holes in theories you don’t like while remaining completely unaware of the absurdity of the alternative you prefer.

    “Does this hold for humans, too?”

    I guess you didn’t read my post very clearly.

    “Forgone conclusion due to test construction. You can believe these tests ‘predict’ this but you’d be in error.”

    This idiot “circularity” objection to IQ test construction is just laughable. Any valid test has to tap the same factors as the activities it’s meant to predict performance in. This will lead to some similarity between the tests and those activities. This is not unique to IQ tests. However IQ tests are predictive of many things they seem to have nothing to do with at first glance. Performance on untimed IQ tests correlates with reaction times, for example. This can be satisfactorily explained only by invoking neurological phenotypes.

    “What is a just-so story?”

    An inadequately supported scientific explanation used to arrive at a conclusion one desires. Since you used the term yourself I would’ve hoped you already knew that.

    “Still waiting for evidence for construct validity.”

    http://psycnet.apa.org/record/2009-11948-008. Not that it matters. You have enough Marxist garbage in your head that there is no amount of evidence you’ll fail to explain away with fallacious babble.

    Read More
    • Replies: @res
    Thanks for that. In particular, thanks for your reference https://www.researchgate.net/publication/267158254_Demonstrating_the_validity_of_twin_research_in_criminology
    Even better, it has supplementary materials available at https://onlinelibrary.wiley.com/doi/abs/10.1111/1745-9125.12049

    Appendix A. Discussion of Additional Assumptions of Twin‐Based Research

    Appendix B. Mathematical Foundations of Behavioral Genetics

    Appendix C. Latent Variable ACE Model

    Appendix D. Comprehensive List of Studies Examining the Equal Environments Assumption

    Appendix E. R Script for Carrying Out Calculations of Assumption Violations
     

    I greatly appreciate having quantitative estimates of the errors corresponding to different sized violations of the model assumptions. I also enjoyed their use of the same George Box quote I mentioned in this comment http://www.unz.com/jthompson/more-genes-for-intelligence-a-pattern-emerges/#comment-2282190

    Since your final reference http://psycnet.apa.org/record/2009-11948-008 is behind a paywall, here are some relevant quotes.


    In Figure 1, latent constructs are represented in the upper left and measures of them are in the upper right. The difference between a construct and its measure is muddied when the terms IQ (a test score) and intelligence (a construct) are used interchangeably, as they commonly are. Test format and content need not mirror what we imagine the unobservable trait or causal force to “look like.” That is why neither item content nor test format provides evidence for or against a test’s validity for measuring the intended latent construct. As noted, test items need only activate the ability under controlled circumstances. Establishing construct validity requires evidence that the behaviour elicited by the test is consistent with propositions about the construct supposedly activated.
     

    We describe two once-plausible alternatives, disproved by the research just reviewed, that are still oft-invoked by testing’s detractors (Gottfredson, 2009). We then turn to how construct-related research has increased our ability not just to rule out such alternatives, but also to evaluate, compare, and improve the construct validity of particular ability tests.
    The once-plausible hypothesis conflates ability and achievement, and the second collapses the distinction between construct and measure. Both reflect the behaviourism of earlier eras in psychology, which eschewed anything not directly observable. The false ability-equals-achievement hypothesis may be paraphrased as follows: Tests of ability (upper right quadrant of Figure 1) actually gauge what an individual already knows or has accomplished in particular content domains (see lower half of Figure 1), not their standing on some hypothesised inner property or a latent construct (i.e., aptness in acquiring the necessary knowledge and skills; see upper left quadrant of Figure 1). ...
     
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  29. If we are to have any chance of moving forward we must actively encourage full spectrum participation and thus suppress the unwarranted advantages provided by family wealth. How can we profess to intelligence if we accept legacy admissions and effectively block all intellectual mobility?
    The great majority of our elites are excessively inbred and useless.

    Read More
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  30. res says:
    @Anonymous
    "In your next comment leave the logical fallacies out of it."

    There are no fallacies in my response. You're one of these idiots who thinks all insults are ad hominems.

    Since your post contains no serious effort to rebut anything I said, but instead offers mere assertions, I'll be similarly lazy in replying.

    "Race is a biological reality."

    Yet you appear to want to deny nearly all the significant factors with respect to which races differ.

    "No and you’re wrong."

    How compelling.

    "Source?"

    http://journals.sagepub.com/doi/abs/10.1177/0956797613493292.

    Somehow you provide no sources in your fatuous reply, but demand that others give sources.

    "Based on?"

    The overwhelming majority of studies that have looked into this matter. If you aren't aware of those, you have no business discussing this subject.

    "Do the interventions change social class?"

    Is social class some magic source of cognitive disablement or advantage that necessarily depresses or raises IQ? Does SES give rise to IQ differences or is it the other way around, and to what degree? The relationship between SES and IQ has been studied countless times. SES obviously cannot explain all variation in IQ because there is enormous variation in IQ within SES categories. Some interventions that have been tried relieve the disadvantages associated with low SES that have been alleged to lower IQ. They still don't work. https://www1.udel.edu/educ/gottfredson/reprints/2005hereditarian-hypothesis.pdf. A major prediction of your environmentalist nonsense fails, and you can't explain why.

    "Irrelevant."

    You think this because you're dumb.

    "Based on assumptions and a computer model. And the twin studies the model used are flawed as well."

    What scientific work doesn't assume certain things? Take a philosophy of science 101 course and get back to me. You're an idiot to think you can dismiss a study simply because it uses a "computer model." Twin studies are sound. If you'd read any recent handbook on behavior genetics you'd be aware that all the halfwit objections from Richardson-types have been answered. In most cases they overestimate the significance of certain assumptions on which twin studies depend, such as the equal environments assumption, which even if false barely makes any difference: https://www.researchgate.net/publication/267158254_Demonstrating_the_validity_of_twin_research_in_criminology https://www.ncbi.nlm.nih.gov/pubmed/24267761.

    "P-FIT is a flawed theory. How do you know the differences in brain area don’t come down to experience? You don’t."

    Even if they come down to experience, IQ tests remain valid. But that is a ridiculous notion because brain development patterns align with the behavior genetic findings. As the simpleton you are, you're oblivious to how ludicrous it is to treat this all as a coincidence.

    IQ differences themselves can be completely environmentally based and IQ tests can still be valid. The fact that you don't realize this shows, again, that you're a moron. P-FIT is certainly in better scientific standing than the IQ-denialist bullshit coming out of your mouth. You're one of these tards who tries to pick holes in theories you don't like while remaining completely unaware of the absurdity of the alternative you prefer.

    "Does this hold for humans, too?"

    I guess you didn't read my post very clearly.

    "Forgone conclusion due to test construction. You can believe these tests ‘predict’ this but you’d be in error."

    This idiot "circularity" objection to IQ test construction is just laughable. Any valid test has to tap the same factors as the activities it's meant to predict performance in. This will lead to some similarity between the tests and those activities. This is not unique to IQ tests. However IQ tests are predictive of many things they seem to have nothing to do with at first glance. Performance on untimed IQ tests correlates with reaction times, for example. This can be satisfactorily explained only by invoking neurological phenotypes.

    "What is a just-so story?"

    An inadequately supported scientific explanation used to arrive at a conclusion one desires. Since you used the term yourself I would've hoped you already knew that.

    "Still waiting for evidence for construct validity."

    http://psycnet.apa.org/record/2009-11948-008. Not that it matters. You have enough Marxist garbage in your head that there is no amount of evidence you'll fail to explain away with fallacious babble.

    Thanks for that. In particular, thanks for your reference https://www.researchgate.net/publication/267158254_Demonstrating_the_validity_of_twin_research_in_criminology
    Even better, it has supplementary materials available at https://onlinelibrary.wiley.com/doi/abs/10.1111/1745-9125.12049

    Appendix A. Discussion of Additional Assumptions of Twin‐Based Research

    Appendix B. Mathematical Foundations of Behavioral Genetics

    Appendix C. Latent Variable ACE Model

    Appendix D. Comprehensive List of Studies Examining the Equal Environments Assumption

    Appendix E. R Script for Carrying Out Calculations of Assumption Violations

    I greatly appreciate having quantitative estimates of the errors corresponding to different sized violations of the model assumptions. I also enjoyed their use of the same George Box quote I mentioned in this comment http://www.unz.com/jthompson/more-genes-for-intelligence-a-pattern-emerges/#comment-2282190

    Since your final reference http://psycnet.apa.org/record/2009-11948-008 is behind a paywall, here are some relevant quotes.

    In Figure 1, latent constructs are represented in the upper left and measures of them are in the upper right. The difference between a construct and its measure is muddied when the terms IQ (a test score) and intelligence (a construct) are used interchangeably, as they commonly are. Test format and content need not mirror what we imagine the unobservable trait or causal force to “look like.” That is why neither item content nor test format provides evidence for or against a test’s validity for measuring the intended latent construct. As noted, test items need only activate the ability under controlled circumstances. Establishing construct validity requires evidence that the behaviour elicited by the test is consistent with propositions about the construct supposedly activated.

    We describe two once-plausible alternatives, disproved by the research just reviewed, that are still oft-invoked by testing’s detractors (Gottfredson, 2009). We then turn to how construct-related research has increased our ability not just to rule out such alternatives, but also to evaluate, compare, and improve the construct validity of particular ability tests.
    The once-plausible hypothesis conflates ability and achievement, and the second collapses the distinction between construct and measure. Both reflect the behaviourism of earlier eras in psychology, which eschewed anything not directly observable. The false ability-equals-achievement hypothesis may be paraphrased as follows: Tests of ability (upper right quadrant of Figure 1) actually gauge what an individual already knows or has accomplished in particular content domains (see lower half of Figure 1), not their standing on some hypothesised inner property or a latent construct (i.e., aptness in acquiring the necessary knowledge and skills; see upper left quadrant of Figure 1). …

    Read More
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