Although these estimates of national IQ are claimed to be "highly valid" (Rushton, 2003, p. 368) or "credible" (McDaniel, 2008, p. 732) by some authors, the work by Lynn (and Vanhanen) has also drawn criticism (Barnett & Williams, 2004; Ervik, 2003; Hunt & Carlson, 2007; Hunt & Sternberg, 2006; Lane, 1994). One point of critique is that Lynn (and Vanhanen)'s estimate of average IQ among Africans is primarily based on convenience samples, and not on samples carefully selected to be representative of a given, targeted, population (Barnett & Williams, 2004; Hunt & Sternberg, 2006). Unfortunately, in many developing countries, such representative samples are lacking (McDaniel, 2008).
A literature review is necessarily selective. Despite Lynn's objective of providing a "fully comprehensive review of the evidence" (Lynn, 2006, p. 2), a sizeable portion of the relevant literature was not considered in both his own review, and in reviews with Vanhanen. Nowhere in their reviews did Lynn (and Vanhanen) specify the details of their literature search. Our own searches in library databases resulted in additional relevant studies that may be used to estimate national IQ. For instance, Lynn and Vanhanen (2006) accorded a national IQ of 69 to Nigeria on the basis of three samples (Fahrmeier, 1975; Ferron, 1965; Wober, 1969), but they did not consider other relevant published studies that indicated that average IQ in Nigeria is considerably higher than 70 (Maqsud, 1980a,b; Nenty & Dinero, 1981; Okunrotifa, 1976). As Lynn rightly remarked during the 2006 conference of the International Society for Intelligence Research (ISIR), performing a literature review involves making a lot of choices. Nonetheless, an important drawback of Lynn (and Vanhanen)'s reviews of the literature is that they are unsystematic. Unsystematic literature reviews do not adhere to systematic methodology to control for potential biases in the many choices made by the reviewer (Cooper, 1998; Light & Pillemer, 1984). Lynn (and Vanhanen) failed to explicate the inclusion and exclusion criteria they employed in their choice of studies. Such criteria act as a filter, and may thus affect the estimate of national IQ. Lynn (and Vanhanen) excluded data from several sources without providing a rationale. For instance, they used IQ data from Ferron (1965), who provided averages in seven samples of children from Sierra Leone and Nigeria on a little-known IQ test called the Leone. For reasons not given, Lynn (2006) and Lynn and Vanhanen (2006) only used data from the two lowest scoring samples from Nigeria. Most of the remaining samples show higher scores, but those samples were not included in the estimation of the national IQ of Nigeria and Sierra Leone. Likewise, Lynn (and Vanhanen) did not consider several relatively high-scoring African samples from South Africa (Crawford Nutt, 1976; Pons, 1974). It is unfortunate that Lynn (and Vanhanen) did not discuss their exclusion criteria. In some cases (Crawford Nutt, 1976; Pons, 1974), the Raven's Progressive Matrices was administered with additional instruction. Although this instruction is quite similar to an instruction as described in the test manual (Raven, Court, & Raven, 1996), some have argued that this instruction artificially enhances test performance (cf. Rushton & Skuy, 2000). Given the likely differences in opinion on which samples to include or exclude in a review, inclusion and exclusion criteria should be explicated clearly and employed consistently. It is well known that unsystematic literature reviews may lead to biased results (Cooper, 1998; Light & Pillemer, 1984). Another problem is that the computation of statistics in literature reviews is quite error-prone. Indeed Lynn's work contains several errors (Loehlin, 2007).
Lynn responded, attempting to defend his work, and Wicherts et al. fired back immediately with an even stronger rejoinder, repeating their previous criticism of his methodology and flat out accusing him of cherry-picking data that supports his position while ignoring the rest:
In this rejoinder, we criticize Lynn and Meisenberg's (this issue) methods to estimate the average IQ (in terms of British norms after correction of the Flynn Effect) of the Black population of sub-Saharan Africa. We argue that their review of the literature is unsystematic, as it involves the inconsistent use of rules to determine the representativeness and hence selection of samples. Employing independent raters, we determined of each sample whether it was (1) considered representative by the original authors, (2) drawn randomly, (3) based on an explicated stratification scheme, (4) composed of healthy test-takers, and (5) considered by the original authors as normal in terms of Socio-Economic Status (SES). We show that the use of these alternative inclusion criteria would not have affected our results. We found that Lynn and Meisenberg's assessment of the samples' representativeness is not associated with any of the objective sampling characteristics, but rather with the average IQ in the sample. This suggests that Lynn and Meisenberg excluded samples of Africans who average IQs above 75 because they deemed these samples unrepresentative on the basis of the samples' relatively high IQs. We conclude that Lynn and Meisenberg's unsystematic methods are questionable and their results untrustworthy.
Then in a later paper, Wicherts et al. dug even deeper, finding that in addition to picking and choosing, Lynn actively seeks out and uses data that's not reliable or representative:
The samples, considered by Lynn (and Vanhanen), but discarded here, are given in the Appendix. Besides the two samples described above (Klingelhofer, 1967; Zindi, 1994), these are Wober's (1969) sample of factory workers, and Verhaegen's (1956) sample of uneducated adults from a primitive tribe in the then Belgian Congo in the 1950s. Verhaegen indicated that the SPM test format was rather confusing to the test-takers, and that the test did not meet the standards of valid measurement. In Wober's study, the reliability and validity were too low (Wober, 1975). In three of the samples in Table 1, the average IQ is below 70. These are Owen's large sample of Black South African school children tested in the 1980s, the 17 Black South Africans carefully selected for their illiteracy by Sonke (2001), and a group of uneducated Ethiopian Jewish children, who lived isolated from the western world in Ethiopia and immigrated to Israel in the 1980s (Kaniel & Fisherman, 1991). The last two samples cannot be considered to be representative.
[...]
Our review of the literature on the performance of Africans on the Raven's tests showed that the average IQ of Africans on the Raven's tests is lower than the average IQ in western countries. However, the average IQ of Africans is not as low as Lynn (and Vanhanen) and Malloy (2008) maintained. The majority of studies on IQ test performance of Africans not taken into account by Lynn (and Vanhanen) and Malloy showed considerably higher average IQs than the studies that they did review. We judge the reviews of Lynn (and Vanhanen) and Malloy to be unsystematic. These authors missed a large part of the literature on IQ testing in Africa, failed to explicate their inclusion and exclusion criteria, and made downward errors in the conversion of raw scores to IQs (Wicherts, 2007). Lynn (and Vanhanen)'s estimate of average IQ of Africans of around 67 is untenable. Our review indicates that it is about 78 (UK norms) or 80 (US norms). These means are somewhat lower than the means of Africans on other IQ tests, which lie around 82 (Wicherts et al., 2010). These results undermine evolutionary theories of race differences in intelligence of Lynn (2006), Rushton (2000), and Kanazawa (2004) (Wicherts, Borsboom, & Dolan, 2010a; Wicherts et al., 2010b).
Lynn responded to that too, accusing Wicherts et al. of deriving their higher estimate of average African IQ from elite samples, but they once again showed that his lower estimate results from the unsystematic use of samples that are not random or representative.
48 comments
So Lynn hasn't been careless (riiight) just with regards to intra-European IQ but also global IQ. Who'd have thought?
What about Rindermann?
He just published a study confirming the relationship between national IQ and wealth. I believe he wasn't convinced by Wicherts data on national IQ.
http://www.psychologicalscience.org/index.php/news/releases/are-the-wealthiest-countries-the-smartest-countries.html
Good to know that Poland will be a powerhouse in the near future, ronny.
"The researchers collected information on 90 countries"
But probably no new IQ tests or anything, just the same old data and extrapolation from PISA scores etc.
If you realize it's off-topic, why did you post it? Did you want to make a point (that probably involves catchphrases such as "PC", "cultural marxism", "multiculturalism") that you can't express clearly?
So black Africans have average IQs that lie somewhere in the 78 to 82 range? How does this undermine Lynn's position that black Africans are less intelligent than white Europeans?
"So black Africans have average IQs that lie somewhere in the 78 to 82 range? How does this undermine Lynn's position that black Africans are less intelligent than white Europeans?"
Because it is politically incorrect to say that some peoples/nations have lower IQ than others.
It is politically incorrect to tell facts to people.
It is politically incorrect to tell the truth to people.
http://www.liveleak.com/view?i=53d_1311690314
Average Joe, that's really beside the point of this blog post. But the fact that African IQ is lower now doesn't mean that it'll always be lower, or that Africans are inherently less intelligent than Europeans (as Lynn and others claim). Ever heard of the Flynn Effect? 80 is a perfectly normal IQ for people living under the conditions Africans are currently subjected to. Wicherts et al. go into all of that.
The real low IQ is Lynn's
"Average Joe, that's really beside the point of this blog post. But the fact that African IQ is lower now doesn't mean that it'll always be lower, or that Africans are inherently less intelligent than Europeans (as Lynn and others claim). Ever heard of the Flynn Effect? 80 is a perfectly normal IQ for people living under the conditions Africans are currently subjected to. Wicherts et al. go into all of that."
Lynn was unsystematic but the situation is more complex than you make it out to be. Wicherts et al
was trying make the best estimate of the IQ of African test takes. To do this they used a rigorous inclusion criteria and excluded numerous samples. Lynn, on the other hand, was trying to estimate the average African IQ, that is, the IQ of Africans if IQ tests were given to representative samples, relative to African conditions. To do this, Lynn made judgement calls about what samples were representative. The difference in objective seems to have led to some of the discrepancy between the estimates. So, for example, Lynn included samples of Africans infected by malaria, arguing that malaria is common to regions in African; Wicherts et al excluded these, arguing that malaria artificially depresses IQ. If the goal is "the average African IQ," Lynn's reasoning seems reasonable -- it gives a base from which one can guesstimate the genotypic IQ.
At any rate, Wicherts et al conclude that the n-weighted average IQ is about 77. (Adjusting for the Flynn effect, assuming a 3 point per decade gain, lowers the n-weighted average slightly). This is close to what Lynn concluded in the 90's, before he adjusted the estimate down. Wicherts et al's estimate, of course, is biased upwards, by virtue of the inclusion criteria. Most of the studies that met the criteria are student studies and Africa has high rates of non-attendance. 77 is probably a good estimate of the IQ of African test takers. But 70 is probably closer to the IQ of the Average african, many of whom are not in school. Lynn's estimate of 70 of course was only intended to be a phenotypic estimate. His genotypic estimates range from 80-90.
.....
The Flynn Effect doesn't seem to be a good explanation for the difference since the difference in IQ between Europeans and Africans has been about the same for the last century. Where there no Flynn effect in Africa one would expect a much larger (about 30 points plus the current) contemporaneous gap. As for African conditions, to some extent Wicherts et al's methodology minimize the difference. It is interesting that the scores of rural Chinese, dating back to the impoverished pre-Deng era, are 1.5+ SD above those of Africans.
>>> "Wicherts et al was trying make the best estimate of the IQ of African test takes. To do this they used a rigorous inclusion criteria and excluded numerous samples. Lynn, on the other hand, was trying to estimate the average African IQ, that is, the IQ of Africans if IQ tests were given to representative samples, relative to African conditions. To do this, Lynn made judgement calls about what samples were representative. The difference in objective seems to have led to some of the discrepancy between the estimates."
"Judgment calls" is a very generous way to describe Lynn's cherry-picking and deception. Wicherts et al. made no such judgment calls. All they excluded from their review were obviously inadequate samples of mentally and physically disabled people, and samples where the test was not administered in its entirety, a time limit was imposed when it shouldn't have been, proper instructions were not given, or there were a lack of appropriate norms.
They included all of the "samples that were based on stratified or clustered random sampling and were deemed representative by the original authors", and then "three independent raters assessed five objective criteria for representativeness of all samples and their ratings showed moderate to almost perfect agreement."
Wicherts et al.'s objective was to provide an accurate estimate of African IQ, while Lynn's objective was to produce the lowest estimate of African IQ possible.
""Judgment calls" is a very generous way to describe Lynn's cherry-picking and deception. Wicherts et al. made no such judgment calls. All they excluded from their review were obviously inadequate samples of mentally and physically disabled people, and samples where the test was not administered in its entirety, a time limit was imposed when it shouldn't have been, proper instructions were not given, or there were a lack of appropriate norms."
The sequence of events is important. First Lynn pioneered the study of national IQs. This is what Jones (2011) says of him:
"Lynn has become the Angus Maddison of national IQ statistics; and just as the popularity of Maddison’s work (inter alia, Maddison 1991) ultimately inspired the creation of large-scale cross-country GDP estimating programs like the canonical Penn World Tables, so too, one can hope that the popularity of Lynn’s data spurs an international effort to assemble rigorous, representative estimates of national average IQ, its higher moments, and its factor structure. (“National IQ and National Productivity: The Hive Mind Across Asia")
Lynn began his pioneering work in the 80's and 90's. The data as Jones notes was initially based on convenience samples. Lynn then wrote his "IQ and the Wealth of nations," "The Global Bell Curve," and "Race differences." After James Watson read one of Lynn's books, he made his now famous comment about African IQ, which prompted Wicherts et al to do a systematic analysis of the African IQ data. Wicherts et al initially concluded that the African IQ based on non-Ravens tests was 78-82, depending on inclusion criteria and based on Raven's tests was about 77, with Flynn corrections.
At this point Lynn could only be faulted for not doing a systematic review of the data. But, again, he was pioneering the idea and did not have multiple hands working on the project. And as it turns out, his National IQs, at least outside of Africa, were more or less sound (as demonstrated by Rindermann 2007, 2011, 2011; Jones 2010, 2011, etc.)
In response to Wicherts et al, Lynn replied, offered new data, and attempted to show that the African IQs were in fact <70. This is where his analysis became questionable and where it makes sense to say that he cherry picked. In counter reply, Wicherts et al pointed out Lynn's selectivity and bias -- in the reply -- and concluded that the n-weighted average (given his inclusion criteria) was about 77.
As I noted though, part of the difference, though, between Lynn's estimate of 68 and Wichert's of 77 is due to differences in goals. In my assessment, Wicherts does not provide an accurate estimate of African IQ, because his methodology overly restricts the range of scores, given the conditions in Africa. To verify this, I went through all the data -- you can contact Wicherts and Lynn for the data sets -- and found an n-weighted IQ of ~74, simply by using all samples (i.e. the most liberal inclusion criteria possible) and reasoning that upwards and downwards biases cancel each other out.
RR, what's up with your site? Are there any working links for it?
@ Chuck
Again, Wicherts et al. make no judgment calls like Lynn does. Their review is systematic and uses objective inclusion criteria. Of course you're going to get a lower IQ estimate than theirs if you include the samples of handicapped people and people who were not permitted to take the test properly. These have nothing to do with "the conditions in Africa". They're just bad, unusable samples.
>>> "RR, what's up with your site? Are there any working links for it?"
Server issues with the host. In the meantime, you can go here.
"Again, Wicherts et al. make no judgment calls like Lynn does. Their review is systematic and uses objective inclusion criteria. Of course you're going to get a lower IQ estimate than theirs if you include the samples of handicapped people and people who were not permitted to take the test properly. These have nothing to do with "the conditions in Africa". They're just bad, unusable samples."
Lynn used similar samples for other countries outside of Africa -- that is, whatever he could find -- and, as Wichert et al notes, the resulting national IQs were not biased in predicting GDP, etc. That calls into question your implication that the methodology was intractably flawed and your assertion that the samples were "unusable." From a theoretical standpoint, as Thomson (2011) notes:
"Criticism of Lynn’s compilation centred on the small sample sizes of many of the studies, and reservations about their representativeness. However, in those cases where larger, epidemiologically sound methodologies have been employed, the results have often been close to those obtained in the original smaller samples. (Richard Lynn’s contributions to personality and intelligence)."
So on both a priori and a posteriori grounds I have to reject your assertion, without denying that Lynn's African national IQs were downwardly biased by about .5SD.
(As for the methodology used by Wicherts et al, you are going to get an inflated value if you use university samples and rely on school samples when there are large attrition rates -- and these were samples that disproportionately fit the criteria, which is why when making adjustments in response to Lynn criticism, Wicherts et al, as discussed in the summary paper, found a, if slightly, lower average IQ then previously.)
However, in those cases where larger, epidemiologically sound methodologies have been employed, the results have often been close to those obtained in the original smaller samples.
That's what I call damning with faint praise.
@ Chuck
If you can't understand why samples of retarded people and people who weren't administered the test properly are unusable, then this discussion is over. Regardless, that isn't "my assertion". It's Wicherts et al.'s assertion and it was verified by independent raters who assessed objective criteria to determine the representativeness of all the available samples. Wicherts' results are not "inflated". They're accurate, unlike Lynn's.
I don't know if Lynn has used any samples quite that egregious in his studies of other countries, but his non-African IQ data is equally questionable, flawed and manipulated in its own way (see here and here, for example). I wouldn't trust anything he does.
"I don't know if Lynn has used any samples quite that egregious in his studies of other countries, but his non-African IQ data is equally questionable, flawed and manipulated in its own way (see here and here, for example). I wouldn't trust anything he does."
If Lynn's data is so untrustworthy, how do you explain it's the predictive power? Here was Rindermann's latest paper:
http://lesacreduprintemps19.files.wordpress.com/2011/08/intellectual-classes-technological-progress-and-economic-development.pdf
Based on an average IQ of 85 for African-Americans, coupled with an average of 20% european admixture we get an average African IQ of ~81. The fact that this jives well with the new estimates makes sense.
@ racialreality
Your making such a weak argument would hardly affect Lynn's credibility at best and your criticisms show you don't understand his work.
The worst you can find on him is that he had a difficult time finding representive samples from Africa. But it is not representive to put such an emphasis on African test takers when they are part of the more elite. He wants the average iq of each population and obviously different populations have different conditions. This is one of the relationshio be wants to study, iq and gdp. And those studies alone aren't meant to prove that the inherent iqs are differnt because he knows living conditions affect iq (the reverse is true too!). He uses other studies to understand why countries have different gdps and different iqs. The point is that he wants the average.
I won't even get into how he knows the population differences are PARTLY genetic...
Also, Lynns argument and the relevance of his findings are not even under threat because even the guy who overestimated the African iq, with more elite samples, still cane up with a low number for Africa.
@ anon
your criticisms show you don't understand the sources posted in OP (you haven't actually read them though so...)
Andreos
O dont believe my eyes - Flynn effect will remove racial differences in IQ??
This effect can only remove some differences, which are a result of a bad environment. But not racial differences in IQ on the whole. For example in USA, better environment (nutrition etc.) lead to increase of IQ of blacks, but also of whites. So, better environment increases IQ-scores of both groups and the basic genetical difference stayed the same - the whole time of the measurement of the IQ (cca 1930 - today), there is a constant difference between whites (IQ 100) and blacks (IQ 84-85) - 15-16 IQ points.
And according Murray, in USA white or Asian children from poor families and with parents with only basic education have still higher SAT-scores than black children from rich families and with parents with university.
So, its clear, that IQ is largely based on our genes, not on environment.
>>> "better environment (nutrition etc.) lead to increase of IQ of blacks, but also of whites. So, better environment increases IQ-scores of both groups and the basic genetical difference stayed the same - the whole time of the measurement of the IQ (cca 1930 - today), there is a constant difference between whites (IQ 100) and blacks (IQ 84-85) - 15-16 IQ points."
Incorrect. The black-white IQ gap has narrowed over the past few decades as blacks have gained 4 to 7 points on whites:
http://www.ncbi.nlm.nih.gov/pubmed/17100793
>>> "And according Murray, in USA white or Asian children from poor families and with parents with only basic education have still higher SAT-scores than black children from rich families and with parents with university."
In the UK, poor black boys outperform poor white boys on achievement tests:
http://racialreality.blogspot.com/2010/06/underperformance-of-poor-white-british.html
Flynn's and Dicken's results show a dropping-off of the IQ gains as blacks age, tho, so that black kids scored about 89, black teenagers at 87, and black young adults at 85. This could be because the (real) gains have only occurred in the youngest generations, but it is also consistent with the theory that 1) phenotypic and genotypic IQ converge as people age, which from what I understand is pretty well-established (though you may know more than I), and 2) black genotypic IQ is around 85, and blacks get a boost from living in a culture/environment created by people with a mean IQ of 100 as kids. I think it's important in this context to note that you see the exact same thing happen with black kids who are adopted by whites: relatively higher IQs in childhood that regress to the black mean as the children age.
With regard to the UK, I suspect that there has been a lot less cognitive sorting among blacks (most of whom are relatively recent arrivals) than there has been among the indigenous population. So you're still getting a lot of untapped potential in the poor black population that has already filtered upward among the white population. Here in the U.S., where blacks have been around a lot longer, poor white boys outperform rich black boys.
>>> Flynn's and Dicken's results show a dropping-off of the IQ gains as blacks age
They took that into account:
"Rushton and Jensen (2006, this issue) concede that the magnitude of the Black-White IQ gap is not immutable, but could have narrowed by as much as 3.44 IQ points, or 0.23 White standard deviations. They concur that the Black-White IQ gap rises with age. Using Shuey's 1966 data, Jensen (1998) estimated a gap of 0.70 standard deviations in early childhood, 1.00 standard deviations in middle childhood, and 1.20 standard deviations in early adulthood. Our current estimates are 0.31 (age 4), 0.63 (age 12), and 0.87 (age 18). Comparison of Jensen's pre-1966 values and our current values yields a Black IQ gain of 0.33 to 0.39 standard deviations. This equals 5.0 to 5.5 IQ points, close to the midpoint of our estimate that Blacks gained 4 to 7 points. Therefore, unless Rushton and Jensen question our current values, our main contention is also conceded. All that is at stake is the timing of the steps by which Blacks progressed from Jensen's values to ours, something we grant to be problematic. And yet, Rushton and Jensen never challenge our values for current Black IQ."
http://www.iapsych.com/iqmr/fe/LinkedDocuments/dickens2006b.pdf
>>> Here in the U.S., where blacks have been around a lot longer, poor white boys outperform rich black boys.
That probably has a lot to do with this:
"Researchers at Brown University's US2010 Project, which analyzes trends in American society, used research from the 2010 U.S. census to find that Black and Latino households earning more than $75,000 a year tended to live in poorer communities than the average lower-income white household that makes less than $40,000 a year. [...] Lower performing schools, high crime rates and lower home values in poorer neighborhoods also explain the disparities, researchers say."
http://www.bet.com/news/national/2011/08/02/wealthy-blacks-live-in-poorer-neighborhoods.html
Still, there are always exceptions:
"Notably, in some areas, the racial gap has been overcome. For example, Latino students in Ohio outperform white students in 13 other states on the eighth grade NAEP reading test and are seven points ahead of the national average. In Texas, low-income black students have the same average score on the fourth grade NAEP as low-income white students in Alabama."
http://www.partnersinschools.org/resources/McKinsey & Co. Report.pdf
RR :
"The black-white IQ gap has narrowed over the past few decades as blacks have gained 4 to 7 points on whites"
New studies proves this statement is false.
http://menghusblog.files.wordpress.com/2012/01/the-totality-of-available-evidence-shows-the-race-iq-gap-still-remains.pdf
See also Gottfredson (p.313) :
http://menghusblog.files.wordpress.com/2012/01/what-if-the-hereditarian-hypothesis-is-true.pdf
It is worthwhile to recall that :
"Individual IQ levels tend to remain unchanged from adolescence onward, and despite strenuous efforts over the past half a century, attempts to raise “g” permanently through adoption or educational means have failed."
(Gottfredson, The General Intelligence Factor)
http://menghusblog.files.wordpress.com/2012/01/the-general-intelligence-factor.pdf
"You take the million or so poorest 3- and 4-year-old children and give them a leg up on socialization and education by providing preschool for them; if it works, it saves money in the long run by producing fewer criminals and welfare recipients — and more productive citizens. [...] It is now 45 years later. We spend more than $7 billion providing Head Start to nearly 1 million children each year. And finally there is indisputable evidence about the program’s effectiveness, provided by the Department of Health and Human Services: Head Start simply does not work."
(Joe Klein, Time to Ax Public Programs That Don’t Yield Results)
http://www.time.com/time/nation/article/0,8599,2081778,00.html
And the Flynn Effect is a big myth :
http://majorityrights.com/weblog/comments/a_possible_explanation_for_the_flynn_effect/
http://analyseeconomique.files.wordpress.com/2011/09/the-secular-rise-in-iqs-in-estonia-the-flynn-effect-is-not-a-jensen-effect.pdf
http://analyseeconomique.files.wordpress.com/2011/09/the-rise-and-fall-of-the-flynn-effect-as-a-reason-to-expect-a-narrowing-of-the-black-white-iq-gap.pdf
http://intelligence.wikeo.be/ze.html#stabilité
Oh, I forgot. You have a stronger evidence here :
http://theunsilencedscience.blogspot.com/2011/09/sats-cohens-d-topography-of-iq.html
Recall that Sat Scores correlates (0.8) with IQ.
So, between 1987 and 2009, Black-White differences widened.
>>> New studies proves this statement is false.
That's not a "new study". It's from 2006, and Dickens & Flynn responded to it.
>>> See also Gottfredson (p.313)
That study is even older, and it's just repeating Rushton & Jensen's arguments.
>>> And the Flynn Effect is a big myth
No, it isn't. Flynn responded to that argument as well.
>>> Oh, I forgot. You have a stronger evidence here
SATs are achievement tests, not general intelligence tests. That isn't "stronger evidence" of anything.
>>> "It's from 2006, and Dickens & Flynn responded to it."
No. Flynn clearly makes a concession. In his paper, he concedes : "Flynn never said real intelligence levels were rising." And ... “Flynn himself . . . does not believe that it shows that blacks can [match whites for IQ] when environments are equal.”
And recall Rushton and Jensen's conclusion in their 2010 paper (and Must paper I pointed above) :
Similarly, the g loadings correlated significantly positively with the Black–White differences (0.53, 0.69) but significantly negatively with the gain scores (mean r=−0.33; range=−0.04 to −0.73; P<0.00001, Fisher, 1970, pp. 99–101). [...] Although the secular gains are on g-loaded tests (such as the Wechsler), they are negatively correlated with the most g-loaded components of those tests. Tests lose their g loadedness over time as the result of training, retesting, and familiarity (te Nijenhuis et al., 2007).
Some good comments on Flynn Effect here:
http://occidentalascent.wordpress.com/2011/05/25/misunderstanding-heritability/
>>> "it's just repeating Rushton & Jensen's arguments"
No. Read page 313.
>>> "SATs are achievement tests"
... that highly correlate (0.82) with "g". The SAT is indeed a very good substitute of IQ test. See also ACT scores. No convergence of the gap :
http://menghusblog.files.wordpress.com/2012/02/white-black-and-white-hispanic-score-gap-in-college-admissions-tests.png
And there is a strong correlation between ACT and SAT scores:
http://www.statcrunch.com/5.0/viewreport.php?reportid=12654
Again, I see no Flynn Effect:
http://intelligence.wikeo.be/ze.html#stabilité
http://majorityrights.com/weblog/comments/a_possible_explanation_for_the_flynn_effect/
A possible explanation for the increase in IQ scores is that children today mature sooner, both physically and mentally, than children did decades ago (Sarich, 1999). Today’s children score higher, not because their real intelligence has increased, but because their brains are more mature. A 10 year old today has a brain that has grown faster and has more neural connections than the brain of a 10 year old who lived, say, 50 years ago. Because today’s 10 year olds have brains that, perhaps, 12 year olds had 50 years ago, they do better on an IQ test taken by 10 year olds 50 years ago. Psychologists think they are comparing identical groups of children – 10 year olds to 10 year olds, but they are actually comparing apples and oranges – 10 year old brains to 12 year old brains.
There is considerable evidence that children today mature earlier. “In the abandoned medieval village of Wharram Percy in Yorkshire, the churchyard has yielded hundreds of skeletons for analysis. There ten-year-olds were around 8in shorter than children today: by the time they were fully grown they were nearly as tall as modern adults.” (Roberts et al., 2005).
A 1997 study of 17,000 American girls (Herman-Giddens et al, 1997) and a British study at Bristol University (Golding, 2000) tracked 14,000 children and found one in six girls with signs of puberty by eight years old, compared to one in 100 a generation ago. “The average age at menarche – when periods start – has plummeted over the past 150 years in western societies from around 17 years old down to 12 or 13.” (Macleod, M., 2007). Boys, too, showed an earlier onset of puberty. (Karpati, 2002).
Similar to the results in Table 2, SAT scores, which correlate 0.8 with IQ scores (Seligman, 1991; Flynn, 1984), dropped at the same time that IQ scores were rising. (Deary, 2001, Chap. 6; Herrnstein et al., 1994, pp. 425-427). If the Flynn Effect is due to an increase in real intelligence then it is difficult to explain why SAT scores would fall at the same time that IQ scores increase.
In Great Britain, there is a reversing of the Flynn Effect:
http://isteve.blogspot.com/2009/02/flynn-flynn-effect-has-reversed-among.html
See two other evidence for the reversing of the flynn effect (Norway, Denmark)
http://www.sciencedirect.com/science/article/pii/S0160289604000522
http://www.iapsych.com/iqmr/fe/LinkedDocuments/teasdale2008.pdf
Steve Sailer has some good comments here:
http://www.vdare.com/articles/flynn-flips-iq-tests-do-matter
According to Flynn, massive IQ increases are not seen in all types of cognitive functioning, just in a couple of areas, which explains why kids these days don't seem all that much smarter, except at programming their new gadgets.
Here are its ten subtests, ranked in order from smallest to largest IQ gain over 55 years: [...] We see only small changes in the first three mental skills: general knowledge , arithmetic, and vocabulary.
In predicting the IQ of a child, mother's IQ is much more important than her SES:
http://menghusblog.files.wordpress.com/2012/03/the-bell-curve-herrnstein-and-murray-graph-19.jpg
All attempts to raise permanently the “g” component of IQ (through adoption and educational means) always failed: Perry Preschool Program, Head Start, etc...
Even if the black-white gap narrowed by a few points, this does not (and never) imply that the black-white gap in achievement and IQ can be completely nullified. IQ is not entirely heritable. In adulthood IQ is 60%-80% heritable. Non-shared environment accounts for the rest of the variance. IQ cannot be easily stimulated.
See McGue and Posthuma:
http://menghusblog.wordpress.com/2012/03/01/increasing-heritability-of-iq-with-age-mcgue-bouchard-iacono-lykken/
http://menghusblog.wordpress.com/2012/02/24/on-heritability-of-iq-brain-size-and-reaction-time-posthuma-de-geus-boomsma/
See also Plomin and Nagoshi:
http://www.sciencedirect.com/science/article/pii/S0160289605000218
http://www.ncbi.nlm.nih.gov/pubmed/16221325
About the "devastating criticism of Richard Lynn" :
"Lynn included samples of Africans infected by malaria, arguing that malaria is common to regions in African; Wicherts et al excluded these, arguing that malaria artificially depresses IQ. If the goal is "the average African IQ," Lynn's reasoning seems reasonable"
In my opinion, chuck says right. As Lynn and Vanhanen already said in a recent (2012) paper:
http://menghusblog.wordpress.com/2012/02/20/national-iqs-a-review-of-their-educational-cognitive-economic-political-demographic-sociological-epidemiological-geographic-and-climatic-correlates/
"... low national IQs are also a cause of widespread infectious diseases because low IQ populations have less understanding of the ways that infections are contracted, and sometimes have erroneous beliefs about how to prevent infection, as suggested by Oesterdiekhoff and Rindermann (2007). In contrast, people with high IQ are better able to avoid infectious diseases by adopting, a prudent lifestyle (for example avoiding HIV infection), and the establishment of effective health care systems."
You cannot interpret poverty strictly as an environmental variable. Environment is, in part, genetically directed.
"Erectus Walks Amongst Us" gives the final blow :
http://erectuswalksamongst.us/
"Even though the percentage of blacks with IQs under 70 is about 6 times the percentage of whites, in one study only 4% of those blacks were actually classified as “retarded,” i.e., as behaviorally impaired, while 15% of the whites were! The reason is not that whites are being discriminated against, but that in whites a low IQ is usually due to a genetic abnormality such as Down’s syndrome, which causes obvious physical deformities, but low IQ blacks usually do not have a genetic defect and are normal in behavior and appearance; in Africans and aborigines these low scores are normal."
"Again, I see no Flynn Effect:"
Damn !
Here is the good link:
http://www.intelligence-humaine.com/genetic.html#stabilité
Stop spamming links to racialist websites. They're not helping your "argument".
>>> No. Flynn clearly makes a concession. In his paper, he concedes :
Those quotes are not from Dickens & Flynn's response regarding whether or not the black-white IQ gap has narrowed, which is what we're talking about. In that response, they show that it's in fact Rushton & Jensen who make concessions:
"Rushton and Jensen (2006, this issue) concede that the magnitude of the Black-White IQ gap is not immutable, but could have narrowed by as much as 3.44 IQ points, or 0.23 White standard deviations. They concur that the Black-White IQ gap rises with age. Using Shuey's 1966 data, Jensen (1998) estimated a gap of 0.70 standard deviations in early childhood, 1.00 standard deviations in middle childhood, and 1.20 standard deviations in early adulthood. Our current estimates are 0.31 (age 4), 0.63 (age 12), and 0.87 (age 18). Comparison of Jensen's pre-1966 values and our current values yields a Black IQ gain of 0.33 to 0.39 standard deviations. This equals 5.0 to 5.5 IQ points, close to the midpoint of our estimate that Blacks gained 4 to 7 points. Therefore, unless Rushton and Jensen question our current values, our main contention is also conceded. All that is at stake is the timing of the steps by which Blacks progressed from Jensen's values to ours, something we grant to be problematic. And yet, Rushton and Jensen never challenge our values for current Black IQ."
http://www.iapsych.com/iqmr/fe/LinkedDocuments/dickens2006b.pdf
>>> And recall Rushton and Jensen's conclusion in their 2010 paper (and Must paper I pointed above)
And recall Flynn's response, which I linked to above:
"You cannot dismiss the score gains of one group on another merely because the reduction of the score gap by subtest has a negative correlation with the g loadings of those subtests. [...] The assertion that 'if population group differences are greater on the more g-loaded and more heritable subtests, it implies they have a genetic origin' is simply false."
http://www.iapsych.com/iqmr/fe/LinkedDocuments/flynn2010a.pdf
>>> No. Read page 313.
I told you, that's an old paper. Dickens & Flynn proved those claims wrong, and Rushton & Jensen conceded.
>>> ... that highly correlate (0.82) with "g". The SAT is indeed a very good substitute of IQ test.
No. Achievement test scores only partly reflect g. They're impacted by many other factors.
"Whereas the correlations indicate that around 50% to 60% of the variance in GCSE examination points score can be statistically explained by the prior g factor, by the same token a large proportion of the variance is not accounted for by g. Some of the remaining variance in GCSE scores will be measurement error, but some will be systematic. Thus, non-g factors have a substantial impact on educational attainment. These may include: school attendance and engagement; pupils' personality traits, motivation and effort; the extent of parental support; and the provision of appropriate learning experiences, teaching quality, school ethos, and structure among other possible factors (Petrides, Chamorro-Premuzic, Frederickson, & Furnham, 2005; Strand, 2003)."
http://www.elsevier.com/authored_subject_sections/S05/S05_357/top/intel.pdf
>>> low national IQs are also a cause of widespread infectious diseases [...] Environment is, in part, genetically directed.
That's complete nonsense for which there's no evidence. Parasite load is objectively higher in the tropics. When Europeans traveled there, they got diseases too, despite their higher intelligence. It's actually the other way around. Widespread infectious disease is a cause of low national IQ. See the following study and read the comments by Dienekes below it:
http://dienekes.blogspot.com/2010/07/parasites-and-intelligence-eppig-et-al.html
"It's actually the other way around. Widespread infectious disease is a cause of low national IQ. See the following study and read the comments by Dienekes below it:"
Well, you finally admit that some of the national IQ differences are real. Here's Jones' recent paper: http://mason.gmu.edu/~gjonesb/IITE.pdf
See his defense of Lynn's data.
As I asked above, if national IQs are meaningless, why all the correlates?
https://lesacreduprintemps19.files.wordpress.com/2012/01/national-iqs-a-review-of-their-educational-cognitive-economic-political-demographic-sociological-epidemiological-geographic-and-climatic-correlates.pdf
Why are the best explanations biological, not cultural:
http://occidentalascent.files.wordpress.com/2011/06/statistical-inference-and-spatial-patterns-in-correlates-of-iq.pdf
Are all these researchers racist? I think the answer to my question is obvious: because the differences are real. This makes Lynn's genetic interpretation a priori plausible.
As for parasite infection, I discussed this elsewhere:
"Personally, I’m a fan of the disease burden hypothesis. Eppig et al. (2010) imply that parasite burden would unlikely result in genetic differences.
But I don’t think that they are looking at it right. Imagine if two population were undergoing identical rates of selection for intelligence. So, for example, in both populations IQ had a heritability of .5 and IQ correlated with SES at .5 and SES correlated with offspring survival at .1. Each generation the genetic IQ of both populations would rise .05 SD (plus .5 x .5 x .1 for the upper 1/3 (i.e., +1 SD) of the IQ distribution and minus .5 x .5 x .1 for the lower 1/3 (i.e., -1 S) of the distribution.) Now enter in disease burden. Imagine that one population was hit by it more than the other. By Eppig et al. (2010)’s “environmental” model (refer to the paper), the IQ selection in the afflicted population would be weakened. (Either because the heritability of IQ would be depressed or because the correlation between IQ and offspring survival would be attenuated.) This could result in a significant divergence in a short time frame (i.e., several hundred years.) Population A could be selected at the rate of .05 SD per generation and population B could be selected at the rate of .02 SD/generation. 17 generations latter or only ~350 years, you would have a 0.5 SD difference."
As for UK IQ, I discussed that here:
http://occidentalascent.wordpress.com/2012/02/07/partially-falsified/
As for the US B-W gap, at most it closed .2 SD. In 2008 the new WAIS norm data showed an increase in the gap. Here is a list of the standardized differences on major IQ tests.
I think your dismissal of Lynn's National IQs is ungrounded. As is your dismissal of a genetic hypothesis. Which isn't to say that I think you're wrong. I'm ambivalent on this issue. I just think your arguments and evidence is poor.
"Rushton and Jensen (2006, this issue) concede that the magnitude of the Black-White IQ gap is not immutable, but could have narrowed by as much as 3.44 IQ points, or 0.23 White standard deviations. They concur that the Black-White IQ gap rises with age"
You left out this part:
"As for the gap of 1.1 standard deviations, the median age in the meta-analysis of Roth et al. would not be under 24. Our Figure 3 projected to age 24.7 gives a current IQ for Blacks of 83.5, or exactly 1.1 standard deviations below Whites."
Now here is what Jensen (1998) said:
"By five to six the mean difference is .7 SD (eleven IQ points), then approaches about 1 SD during elementary school years. remaining fairly constant until puberty, when it increases slightly and stabilizes at about 1.2 SD."
So, comparing Flynn's data, the decrease was about .4 SD at age 4. .37 SD at age 12. .33 SD at age 18. And .1 SD in adulthood. Conspicuously, there is little decrease by adulthood, when IQ is most heritable.
It's perhaps more instructive to look at the means across tests. Flynn and Dickens base their estimates on 4 IQ tests. Going with the most recent norms for the tests they used: in 2002, the WISC difference was 0.78 SD, compared to 1.15 in the 70s; in 2008, the WAIS difference was 1.06 SD, compared with 1.01 in the 70s; in 1997, the AFQT difference was .99 SD, compared with 1.23 in the 80s; in 2001 the SB difference was .77 SD, compared with .9 in the 80s. The average closure is .175 SD. I don't see where the 5-6 points is coming from.
Seems highly dependent on the mode of analysis.
>>> Well, you finally admit that some of the national IQ differences are real.
I never denied that IQ differences are real. I only said that Lynn's data is inaccurate and unreliable, which is a proven fact, and that his theories are unsupported.
>>> Jones' recent paper: [...] See his defense of Lynn's data.
I don't see any such thing. He mentions Wicherts' criticism a few times, mostly just reiterating it, but doesn't defend Lynn's inaccurate estimate of African IQ. He only says that both Lynn and Wicherts agree that African IQ is comparatively low, which is beside the point and irrelevant.
>>> As I asked above, if national IQs are meaningless, why all the correlates?
(1) I never said IQ was "meaningless". (2) Correlations tell us nothing about causality. And (3) Lynn and his gang manipulate data to fit their conclusions.
>>> Why are the best explanations biological, not cultural:
The study you linked to confirms Eppig's parasite burden explanation, so I'm not sure what you're referring to.
>>> I don't see where the 5-6 points is coming from.
I don't know enough about the subject to evaluate the data myself, but I trust Dickens & Flynn, and Rushton & Jensen never challenged their rebuttal.
Oh, about what you previously said :
"Parasite load is objectively higher in the tropics. When Europeans traveled there, they got diseases too, despite their higher intelligence."
Baker denies it.
"The explorers certainly do not present a picture of universal sickness among the inhabitants of the inland parts of Africa. Du Chaillu says of the Ashira (Pan 1), 'The natives are generally tolerably healthy. I have seen cases of what I judge the leprosy, but they have little fever among them, or other dangerous diseases.' ... Galton says of Ovamboland that 'There are no diseases in these parts except slight fever, frequent ophthalmia, and stomach complaints.' ... he [Schweinfurth] remarks that 'My health was by no means impaired, but, on the contrary, I gained fresh vigour in the pure air of the southern highlands.' ... he [Livingstone] remarked that the hilly ridges of this region 'may even be recommended as a sanatorium for those whose enterprise leads them on to Africa. ... they afford a prospect to Europeans, of situations superior in point of salubrity to any of those on the coast'. He says also that '... they resemble that most healthy of all healthy climates, the interior of South Africa, near and adjacent to the [Kalahari] Desert'." (p. 399-400)
Regarding what Wicherts et al. assert, in my view, it does not matter if they are right. If R. Lynn is wrong, the Hereditarian Hypothesis is strengthened.
^ You don't know what you're talking about. Tropical Africa has the most infectious disease, and Europeans did get sick when they went there.
>>> If R. Lynn is wrong, the Hereditarian Hypothesis is strengthened.
No.
Your argument is really weak, I'm disappointed. The fact is that the countries and regions explored by Du Chaillu, Livingstone and co. are unaffected by such diseases. This demonstrates that whether africans are unhealthy or healthy, they are still poor, in both cases. Again, I suggest you read Baker's book, especially pages 397, 398, 399, 400 and 528.
Even if you're right, you fail to demonstrate that the IQ differences around the world are entirely due to environment/culture. See here. See also Rushton and Jensen, page 26.
"Winick et al. [160] studied 141 Korean children malnourished-in-infancy and then adopted as infants by American families. They found that by 10 years of age the children exceeded the national average in IQ and achievement scores: A severely-malnourished group obtained a mean IQ of 102; a moderately-nourished group obtained a mean IQ of 106; and an adequately-nourished group obtained a mean IQ of 112."
The first link you provided me is unconvincing. Treopod had responded to you, here. This link points out that the child death in India rate is the "highest in the world". And Baker had already noted that India 1/ is filled with disease (and not much worse than Africa) 2/ made "great advances in intellectual life" (p. 399). Regarding the third link, chuck responded to you.
I also recommend this book (see chapter 24). But chapter 15-16 are also of interest.
http://analyseeconomique.files.wordpress.com/2011/11/understanding-human-history.pdf.
Finally, one question. If Africans were so intelligent and capable, and that their low intelligence is primarily or entirely due to environment, which means that some S.S. african countries are hard to live in, why didn't they leave these unhealthy countries in a remote past ? Why didn't they move to the north ? My guess is that they were initially not really capable at all.
I suggest you learn how to read because Chuck's "response" was just rhetorical speculation, and I refuted all of Treopod's arguments. Child deaths are irrelevant since those children never grow up to affect national IQs. Besides, that report is misleading. India has the highest overall number of child deaths because it's the second most populous country in the world. But the infant mortality rate is actually highest in Africa.
That quote about Korean infants clearly demonstrates the effect of malnutrition on IQ, which results in a 10-point difference even in those favorable circumstances! Now increase the levels of malnutrition to the highest on earth, add infectious disease to the equation, then subtract immediate escape from that environment to America, and maybe you can understand why African IQ would be so much lower.
Your final question and "guess" are both idiotic. It doesn't take a high IQ to migrate. Our less intelligent ancestors did it more often than we do, as did Neanderthals and even animals. And the infectious diseases that are present in Africa today were not necessarily there in the remote past. For example AIDS, which is now ravaging the continent, didn't exist until very recently.
P.S. Most of your sources are a joke on the same level as Lynn. Rushton is a eugenicist who heads the white supremacist Pioneer Fund and contributes to American Renaissance. Jensen collaborates with Rushton, and the PF bankrolls their research. And Hart is a segregationist who speaks at AR conferences.
"Child deaths are irrelevant since those children never grow up to affect national IQs."
It's not irrelevant, because child death reflects the unhealthiness of the whole country.
"It doesn't take a high IQ to migrate."
If you want to "expel" another population, it is necessary to have a higher IQ than those who already live in the northern parts of Africa, or elsewhere. This is one of the many flaws with "Out of Africa".
"That quote about Korean infants clearly demonstrates the effect of malnutrition on IQ, which results in a 10-point difference even in those favorable circumstances!"
And ? This is exactly what Lynn asserts. Personally, I believe that nutrition is very likely to produce less than 10 points. 1/ These Koreans were young when tested. 2/ Rushton finds that the IQ of mixed-race in South africa is as high as 80 or 83.
3/ Charles Murray believes that the IQ of afro-americans is ... overestimated. See page 314.
fyi. Chuck has a new post with Lynn & Meisenberg's paper. Meisenberg and Lynn, 2011. Intelligence: A Measure of Human Capital in Nations
@Meng Hu - Unhealthiness of the country is a factor that affects IQ. It helps strengthen Wicherts and Flynn's point.
"If you want to "expel" another population, it is necessary to have a higher IQ than those who already live in the northern parts of Africa, or elsewhere. This is one of the many flaws with "Out of Africa"."
This makes no sense. There is no evidence that the relatively higher IQs in northern Africa (1) which is still relatively low compared to the West; and 2) much of North Africa still has large populations of black people, such as Sudan, Egypt and Libya) and high-IQ is not needed to migrate. Tribesmen with no formal education migrate all the time, including the Khoi peoples who reportedly have some of the lowest average IQs around.
"And ? This is exactly what Lynn asserts. Personally, I believe that nutrition is very likely to produce less than 10 points."
Tests administered on adult North Koreans have shown them up to a full standard deviation behind the average IQs in South Korea.
Also, this hereditarian myth that your genes aren't fully expressed until adulthood is just that: a myth. Your genes are already more or less fully expressed by the age of 8-11. All that happens afterwards is puberty, not gene expression.
Even if IQ were highly hereditary (which hasn't proven to be, it's as low as 0.1 heritability for poor minorities in the US), heritable does not mean "set in stone" or "destiny" like most hereditarians seem to think it means. I think they misunderstand what "heritable" means.
http://www.guardian.co.uk/science/2009/nov/12/race-intelligence-iq-science
Also, there has never been any evidence there is any correlation between European admixture in black Americans and IQ. A test of black people of different admixtures showed no real pattern in IQ differentiation.
Sloppy science. Who'd have thought? lol
It is so sad to read that the decedents of centuries of slavery and suppression are being devaluated as being inferior.
As if the poorest whites, whose families stems from generations of severe poverty today will meet the same level as the whites whose families live for generations as an elite.
Strange comparison, isn’t it?
This blog is really amazing, thank you.
Watch exciting Arab porn sites through the following addresses.
bd sex videoمشاهدة نيك محارم
bd sex videoسكسعرب نسوانجي
bd sex videoمشاهدة سكس محارم
bd sex videoسكس نسوانجي عربي
bd sex videoتحميل سكس امريكي
bd sex videoسكس محارم اجنبي
صور نيك
I think this is among the most significant info for me.
먹튀검증 토토사이트
Post a Comment
Be civil. Write clearly. Proofread and preview. Don't troll or spam. Stay on topic.