{"id":4132,"date":"2014-02-27T21:14:40","date_gmt":"2014-02-27T20:14:40","guid":{"rendered":"http:\/\/emilkirkegaard.dk\/en\/?p=4132"},"modified":"2017-05-31T18:31:25","modified_gmt":"2017-05-31T17:31:25","slug":"educability-and-group-differences-arthur-jensen-1973","status":"publish","type":"post","link":"https:\/\/emilkirkegaard.dk\/en\/2014\/02\/educability-and-group-differences-arthur-jensen-1973\/","title":{"rendered":"Educability and group differences (Arthur Jensen, 1973)"},"content":{"rendered":"<p><a href=\"https:\/\/www.goodreads.com\/book\/show\/786753.Educability_And_Group_Differences\">https:\/\/www.goodreads.com\/book\/show\/786753.Educability_And_Group_Differences<\/a><\/p>\n<p><a href=\"http:\/\/gen.lib.rus.ec\/book\/index.php?md5=501f355b6e474bdc0b7f3130dc3bf9c0&amp;open=0\">http:\/\/gen.lib.rus.ec\/book\/index.php?md5=501f355b6e474bdc0b7f3130dc3bf9c0&amp;open=0<\/a><\/p>\n<p>&nbsp;<\/p>\n<p>Why read a book from 1973? 41 years old? Well, it was a good read indeed! It is interesting how much of the evidence for racial differences were in place already in 1973, and it has more or less only become stronger since then. Basically, the book is a shorter and less technical (but not that much!) version of his major book <em>The g Factor<\/em>.<\/p>\n<p>&nbsp;<\/p>\n<p>&#8212;<\/p>\n<p>&nbsp;<\/p>\n<p><em>This distinction between the individual and the particular gene pool from which the unique combination forming his genotype was derived extends beyond his family to the racial group with which he is identified and to the social status into which he is born. You are not your race; you are not your group. You are you. That is, if you are talking genetics. If you are talking sociology or politics, that may be another matter. You may be psychologically tied to and influenced by whatever groups you happen to identify with. If you are either elated or depressed about yourself because of such identification, don\u2019t attribute this to genetics. It in fact contradicts this kind of typology which compels so many persons to identify with various groups as if the statistical attributes of the group determined their own characteristics. Racism and social elitism fundamentally arise from identification of individuals with their genetic ancestry; they ignore individuality in favor of group characteristics; they emphasize pride in group characteristics, not individual accomplishment; they are more concerned with who belongs to what, and with head-counting and percentages and<\/em><br \/>\n<em>quotas than with respecting the characteristics of individuals in their own right. This kind of thinking is contradicted by genetics; it is anti-Mendelian. And even if you profess to abhor racism and social elitism and are joined in battle against them, you can only remain in a miserable quandary if at the same time you continue to think, explicitly or implicitly, in terms of non-genetic or anti-<\/em><br \/>\n<em>genetic theories of human differences. Wrong theories exact their own penalties from those who believe them. Unfortunately, among many of my critics and among many students I repeatedly en\u00ad<\/em><br \/>\n<em>counter lines of argument which reveal disturbing thought-blocks to distinguishing individuals from statistical characteristics (usually the mean) of the groups with which they are historically or socially identified. I know professors, for example, who cannot bring themselves to discuss racial group differences when any persons from different racial groups are present, and the fact that I am<\/em><br \/>\n<em>able to do so perhaps makes me appear insensitive in their eyes. I was once bothered by this too. I got over it as I studied more genetics and came more and more to appreciate its real implications.<\/em><\/p>\n<p>&nbsp;<\/p>\n<p>Well written! I had the same idea, namely that what unites racists and &#8216;antiracists&#8217; is their collectivism, their focus on the properties of groups instead of individuals.<\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">The important distinction between the individual and the <\/span><\/p>\n<p><span style=\"color: #800000;\">populationmust always be kept clearly in mind in any discussion <\/span><\/p>\n<p><span style=\"color: #800000;\">of racial differences in mental abilities or any behavioral charac\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">teristics. Whenever we select a person for some special educa\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">tional purpose, whether for special instruction in a grade-school <\/span><\/p>\n<p><span style=\"color: #800000;\">class for children with learning problems, or for a \u2018gifted\u2019 class <\/span><\/p>\n<p><span style=\"color: #800000;\">with an advanced curriculum, or for college attendance, or for <\/span><\/p>\n<p><span style=\"color: #800000;\">admission to graduate training or a professional school, we are<\/span><\/p>\n<p><span style=\"color: #800000;\">selecting an individual, and we are selecting him and dealing <\/span><\/p>\n<p><span style=\"color: #800000;\">with him as an individual for reasons of his individuality. <\/span><\/p>\n<p><span style=\"color: #800000;\">Similarly, when we employ someone, or promote someone in <\/span><\/p>\n<p><span style=\"color: #800000;\">his occupation, or give some special award or honor to someone <\/span><\/p>\n<p><span style=\"color: #800000;\">for his accomplishments, we are doing this to an individual. <\/span><\/p>\n<p><span style=\"color: #800000;\">The variables of social class, race, and national origin are <\/span><\/p>\n<p><span style=\"color: #800000;\">correlated so imperfectly with any of the valid criteria on which <\/span><\/p>\n<p><span style=\"color: #800000;\">the above decisions should depend, or, for that matter, with any <\/span><\/p>\n<p><span style=\"color: #800000;\">behavioral characteristic, that these background factors are irre\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">levant as a basis for dealing with individuals &#8211; as students, as <\/span><\/p>\n<p><span style=\"color: #800000;\">employees, as neighbors. Furthermore, since, as far as we know, <\/span><\/p>\n<p><span style=\"color: #800000;\">the full range of human talents is represented in all the major <\/span><\/p>\n<p><span style=\"color: #800000;\">races of man and in all socioeconomic levels, it is unjust to allow <\/span><\/p>\n<p><span style=\"color: #800000;\">the mere fact of an individual\u2019s racial or social background to <\/span><\/p>\n<p><span style=\"color: #800000;\">affect the treatment accorded to him. All persons rightfully must <\/span><\/p>\n<p><span style=\"color: #800000;\">be regarded on the basis of their individual qualities and merits, <\/span><\/p>\n<p><span style=\"color: #800000;\">and all social, educational, and economic institutions must have <\/span><\/p>\n<p><span style=\"color: #800000;\">built into them the mechanisms for insuring and maximizing <\/span><\/p>\n<p><span style=\"color: #800000;\">the treatment of persons according to their individual behavior.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>As written by a true racist, or something&#8230;<\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">A common misconception often arises in connection with standards <\/span><\/p>\n<p><span style=\"color: #800000;\">such as the following from an article by Dreeben (1969): \u2018First, <\/span><\/p>\n<p><span style=\"color: #800000;\">genetic forces and environmental forces operate on two distinct <\/span><\/p>\n<p><span style=\"color: #800000;\">dimensions of time. Genetic effects are established when an ovum<\/span><\/p>\n<p><span style=\"color: #800000;\">is fertilized &#8211; at one moment in time; environmental effects extend <\/span><\/p>\n<p><span style=\"color: #800000;\">over time.\u2019 This is often erroneously believed to mean that although <\/span><\/p>\n<p><span style=\"color: #800000;\">individuals may be endowed with different genotypes at the moment <\/span><\/p>\n<p><span style=\"color: #800000;\">of conception, all change and differentiation that take place <\/span><\/p>\n<p><span style=\"color: #800000;\">thereafter are the result of environmental forces. But this interpreta\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">tion overlooks the fact that the genes exert a continuing influence <\/span><\/p>\n<p><span style=\"color: #800000;\">on developmental processes. Many genetic effects are manifested <\/span><\/p>\n<p><span style=\"color: #800000;\">phenotypically only in later stages of development. As an obvious <\/span><\/p>\n<p><span style=\"color: #800000;\">example, patterns of baldness are genetically determined but do <\/span><\/p>\n<p><span style=\"color: #800000;\">not show up until middle age. Behavioral characteristics associated <\/span><\/p>\n<p><span style=\"color: #800000;\">with maturational processes, like mental development, variously <\/span><\/p>\n<p><span style=\"color: #800000;\">manifest genetic effects increasingly as the individual grows from <\/span><\/p>\n<p><span style=\"color: #800000;\">infant to adult. This is clearly seen in the gradually increasing <\/span><\/p>\n<p><span style=\"color: #800000;\">degree of correlation between the mental abilities of parents and <\/span><\/p>\n<p><span style=\"color: #800000;\">their biological children from infancy to late adolescence, which <\/span><\/p>\n<p><span style=\"color: #800000;\">occurs even when the children have never had contact with their <\/span><\/p>\n<p><span style=\"color: #800000;\">biological parents after infancy and have been reared by adoptive <\/span><\/p>\n<p><span style=\"color: #800000;\">or foster parents (e.g., Honzik, 1957). Under a normal range of <\/span><\/p>\n<p><span style=\"color: #800000;\">environmental conditions, an individual\u2019s phenotypic IQ, from <\/span><\/p>\n<p><span style=\"color: #800000;\">infancy to maturity, converges toward its genotypic value.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>So, it was known that heritability increases already in 1957 (or 1973). I thought it entered common knowledge in 1994 with McGue M, Bouchard TJ, Jr, Iacono WG, Lykken DT. 1993. Behavior genetics of cognitive ability: A life-span perspective.<\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">Probably the best evidence for the threshold hypothesis would <\/span><\/p>\n<p><span style=\"color: #800000;\">be the finding of significantly higher heritability in groups that <\/span><\/p>\n<p><span style=\"color: #800000;\">are above average in SES and environmental advantages than in <\/span><\/p>\n<p><span style=\"color: #800000;\">groups of low SES.13 No one has ever done this systematically. <\/span><\/p>\n<p><span style=\"color: #800000;\">The gifted children in Terman\u2019s study came mostly from the <\/span><\/p>\n<p><span style=\"color: #800000;\">higher SES levels and unquestionably had considerably better <\/span><\/p>\n<p><span style=\"color: #800000;\">than average environmental advantages for intellectual develop\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">ment. The mean IQ of their siblings was 123 and the correlation <\/span><\/p>\n<p><span style=\"color: #800000;\">between the IQs of the gifted and their siblings, estimated from <\/span><\/p>\n<p><span style=\"color: #800000;\">the sibling regression, is 0-44, which, when corrected for attenu\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">ation, is close to the genetically predicted sibling correlations of <\/span><\/p>\n<p><span style=\"color: #800000;\">0*5 (with random mating) or 0-6 (with an assortative mating <\/span><\/p>\n<p><span style=\"color: #800000;\">coefficient of 0-5), and does not differ much from sibling correla\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">tions reported in the general literature. The gifted group as adults <\/span><\/p>\n<p><span style=\"color: #800000;\">were, on the average, of higher SES than their own parents. Thus <\/span><\/p>\n<p><span style=\"color: #800000;\">the offspring of the gifted probably enjoyed even greater environ\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">mental advantages. The narrow heritability of IQ in this group, <\/span><\/p>\n<p><span style=\"color: #800000;\">estimated from the midparent-midchild regression, is 0-85. This <\/span><\/p>\n<p><span style=\"color: #800000;\">is significantly higher than the best estimate of narrow&#8217; heritability <\/span><\/p>\n<p><span style=\"color: #800000;\">(0*71) given by Jinks and Fulker (1970, p. 342) on the basis of <\/span><\/p>\n<p><span style=\"color: #800000;\">Burt\u2019s data, which includes a wride range of SES in the English <\/span><\/p>\n<p><span style=\"color: #800000;\">population. It is also higher than the midparent-midchild correla\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">tion (0-69 + 0-03) found in a largely rural population sample in <\/span><\/p>\n<p><span style=\"color: #800000;\">Vermont in 1920, with environmental advantages presumably <\/span><\/p>\n<p><span style=\"color: #800000;\">much below those provided by the Terman gifted and their <\/span><\/p>\n<p><span style=\"color: #800000;\">spouses (Jones, 1928, p. 69). These heritability findings, then, are<\/span><\/p>\n<p><span style=\"color: #800000;\">consistent with the threshold hypothesis. But the total evidence <\/span><\/p>\n<p><span style=\"color: #800000;\">for the hypothesis must still be regarded as quite ambiguous. A <\/span><\/p>\n<p><span style=\"color: #800000;\">clear finding of an appreciable difference between h2 in the Negro <\/span><\/p>\n<p><span style=\"color: #800000;\">and white populations, however, would be consistent with the <\/span><\/p>\n<p><span style=\"color: #800000;\">hypothesis depicted in Figures 7*5 and 7*6. It could mean, in <\/span><\/p>\n<p><span style=\"color: #800000;\">effect, that the scale of environmental effects differs for the bulk <\/span><\/p>\n<p><span style=\"color: #800000;\">of the two populations and not simply that the two populations are <\/span><\/p>\n<p><span style=\"color: #800000;\">distributed about different means on the same additive (i.e., equal <\/span><\/p>\n<p><span style=\"color: #800000;\">interval) scale of environments. So now we must examine what <\/span><\/p>\n<p><span style=\"color: #800000;\">meager evidence exists on the estimation of h2 in Negro populations.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>With all the talk about h2 x SES interactions, Jensen was there 40 years ago too. :p<\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">A statistical test could be applied to determine if the lesser <\/span><\/p>\n<p><span style=\"color: #800000;\">variance of the Negro IQ distribution is an artifact of the scale or <\/span><\/p>\n<p><span style=\"color: #800000;\">a \u2018fact of nature\u2019. One would determine, for both Negro and white <\/span><\/p>\n<p><span style=\"color: #800000;\">population samples, separately and together, whether there is any <\/span><\/p>\n<p><span style=\"color: #800000;\">significant correlation (both linear and non-linear relationships <\/span><\/p>\n<p><span style=\"color: #800000;\">should be sought) between family means (based on fraternal twins <\/span><\/p>\n<p><span style=\"color: #800000;\">or siblings7) and within-family variances. Since the total variance <\/span><\/p>\n<p><span style=\"color: #800000;\">( V T) of a subpopulation is comprised of the between-families <\/span><\/p>\n<p><span style=\"color: #800000;\">variance ( VB) plus within-families variance ( V w), we should <\/span><\/p>\n<p><span style=\"color: #800000;\">determine if two subpopulations which differ in VT differ in VB<\/span><\/p>\n<p><span style=\"color: #800000;\">or Vw or in both. If they differ only in VB, this suggests a \u2018fact of <\/span><\/p>\n<p><span style=\"color: #800000;\">nature\u2019 rather than an artifact of scale, and this interpretation is <\/span><\/p>\n<p><span style=\"color: #800000;\">strengthened if it is found that there is no significant correlation <\/span><\/p>\n<p><span style=\"color: #800000;\">between family means and within-family variances. A correlation <\/span><\/p>\n<p><span style=\"color: #800000;\">between within-family variances and family means suggests a <\/span><\/p>\n<p><span style=\"color: #800000;\">scale artifact which might be eliminated by a transformation of <\/span><\/p>\n<p><span style=\"color: #800000;\">the scale. These tests, however, would not be worthwhile unless <\/span><\/p>\n<p><span style=\"color: #800000;\">performed on quite large and representative samples of the sub\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">populations in question. If it is found that the most adequate scale <\/span><\/p>\n<p><span style=\"color: #800000;\">from all these standpoints shows marked differences in IQ variance <\/span><\/p>\n<p><span style=\"color: #800000;\">for Negroes and whites, and if the heritabilities of IQ were either <\/span><\/p>\n<p><span style=\"color: #800000;\">closely comparable in both populations, or smaller in the Negro <\/span><\/p>\n<p><span style=\"color: #800000;\">population, the genetic uniformity hypothesis would be very <\/span><\/p>\n<p><span style=\"color: #800000;\">untenable. It would indicate less genetic variance in the Negro <\/span><\/p>\n<p><span style=\"color: #800000;\">population. (The results could, of course, go in the opposite <\/span><\/p>\n<p><span style=\"color: #800000;\">direction, but the evidence based on the existing scales of mental <\/span><\/p>\n<p><span style=\"color: #800000;\">ability indicates less variance in the Negro samples.) Smaller <\/span><\/p>\n<p><span style=\"color: #800000;\">variance, with the consequence of a lesser proportion of the <\/span><\/p>\n<p><span style=\"color: #800000;\">subpopulation having higher values on the intellectual ability<\/span><\/p>\n<p><span style=\"color: #800000;\">scale, even if the mean were the same as in the general population, <\/span><\/p>\n<p><span style=\"color: #800000;\">would have important social consequences for the subpopulation <\/span><\/p>\n<p><span style=\"color: #800000;\">with the lower variance in terms of the proportion of its members <\/span><\/p>\n<p><span style=\"color: #800000;\">who are able to compete successfully in those endeavors in which <\/span><\/p>\n<p><span style=\"color: #800000;\">proficiency is most highly correlated with intellectual ability. <\/span><\/p>\n<p><span style=\"color: #800000;\">J. B. S. Haldane (1965, pp. xcii-xciii) noted that \u2018For cultural <\/span><\/p>\n<p><span style=\"color: #800000;\">achievements high variability may be more important than a high <\/span><\/p>\n<p><span style=\"color: #800000;\">average. . . . When we say the ancient Greeks were great mathe\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">maticians we are in fact thinking of about 20 men. We know <\/span><\/p>\n<p><span style=\"color: #800000;\">nothing about the average Greeks in this respect.\u2019<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">Why should two populations have different genetic variances? <\/span><\/p>\n<p><span style=\"color: #800000;\">Differences in gene frequencies and in the degree of assortative <\/span><\/p>\n<p><span style=\"color: #800000;\">mating are the chief causes.8 A difference in gene frequencies for <\/span><\/p>\n<p><span style=\"color: #800000;\">a given characteristic will cause different means and variances, <\/span><\/p>\n<p><span style=\"color: #800000;\">although if the number of gene loci is large, the difference in <\/span><\/p>\n<p><span style=\"color: #800000;\">variances will be relatively less than the difference in means. If <\/span><\/p>\n<p><span style=\"color: #800000;\">the genetic means in both populations are equal, the most likely <\/span><\/p>\n<p><span style=\"color: #800000;\">explanation of unequal genetic variances is differences in degree <\/span><\/p>\n<p><span style=\"color: #800000;\">of assortative mating. That is, the tendency for like to mate with <\/span><\/p>\n<p><span style=\"color: #800000;\">like with respect to a particular trait. It is known that there is a <\/span><\/p>\n<p><span style=\"color: #800000;\">high degree of assortative mating for intelligence in the white <\/span><\/p>\n<p><span style=\"color: #800000;\">population. (There are no published studies of assortative mating <\/span><\/p>\n<p><span style=\"color: #800000;\">for intelligence in non-white populations.) Assortative mating <\/span><\/p>\n<p><span style=\"color: #800000;\">increases the total genetic variance in the population; it also <\/span><\/p>\n<p><span style=\"color: #800000;\">increases the between-families variance relative to within-families <\/span><\/p>\n<p><span style=\"color: #800000;\">variance. Some 15 to 20 percent of the total variance in the white <\/span><\/p>\n<p><span style=\"color: #800000;\">population is attributable to assortative mating for intelligence. <\/span><\/p>\n<p><span style=\"color: #800000;\">Assortative mating per se has no effect on the mean, so if both the <\/span><\/p>\n<p><span style=\"color: #800000;\">genetic means andvariances differ between two populations, we <\/span><\/p>\n<p><span style=\"color: #800000;\">can suspect differences in gene frequencies as well as differences <\/span><\/p>\n<p><span style=\"color: #800000;\">in assortative mating.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>This is interesting. Especially if the assortative mating might be increased due to internet dating. This could have big social implications. With IQ 100, SD 15, 2.3% are &gt;130. But if we increased variance 10% cuz of stronger assortative mating, it wud be 3.45% above. The effects are huge when we get farther out. Ofc, on the other hand, it will also give me imbeciles. Im willing to take the trade. :p<\/p>\n<p>&nbsp;<\/p>\n<p>As for the unequal variances between races with africans having <em>less<\/em>. This seems implausible in the light of the fact that africans have higher variance in all genes. So, it wud be odd if they had lower variance in the <em>g<\/em>-genes.<\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">Since variation in skin pigmentation, because of its social- <\/span><\/p>\n<p><span style=\"color: #800000;\">environmental consequences, is controlled in this research design, <\/span><\/p>\n<p><span style=\"color: #800000;\">any direct biochemical connection between degree of skin pig\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">mentation and intelligence must be either ruled out or, if such a <\/span><\/p>\n<p><span style=\"color: #800000;\">relationship is established, its consequences for the present design <\/span><\/p>\n<p><span style=\"color: #800000;\">must be assessed. The possibility of a biochemical connection<\/span><\/p>\n<p><span style=\"color: #800000;\">between skin pigmentation and intelligence is not totally unlikely <\/span><\/p>\n<p><span style=\"color: #800000;\">in view of the biochemical relation between melanins, which are <\/span><\/p>\n<p><span style=\"color: #800000;\">responsible for pigmentation, and some of the neural transmitter <\/span><\/p>\n<p><span style=\"color: #800000;\">substances in the brain. The skin and the cerebral cortex both arise <\/span><\/p>\n<p><span style=\"color: #800000;\">from the ectoderm in the development of the embryo and share <\/span><\/p>\n<p><span style=\"color: #800000;\">some of the same biochemical processes.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>And it now makes sense that Jensen later wrote his comment in: Jensen, Arthur R. &#8220;Comments on correlations of IQ with skin color and geographic\u2013demographic variables.&#8221; <em>Intelligence<\/em> 34.2 (2006): 128-131.<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">Templer and Arikawa emphasize that they regard skin color only as a climatic variable, a multigenerational reflection of climatic history. And this may well be theoretically adequate for their present purpose. But we should not let it mislead us to dismiss completely other possible, and presently causal, connections between skin color and IQ\u2014an idea the authors, perhaps too cautiously, called \u201cabsurd.\u201d This stance overlooks the probability of the genetic phenomenon of <\/span><em><span style=\"color: #800000;\">pleiotropy<\/span><\/em><span style=\"color: #800000;\"> acting as at least a partial cause of the IQ\u00a0\u00d7\u00a0skin color correlation in present day populations. (Pleiotropy is the condition of a single gene having two or more phenotypically quite different effects. For example a single gene could affect both IQ and skin color.) <\/span><\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">But the whole notion of equating for SES, in the first place, <\/span><\/p>\n<p><span style=\"color: #800000;\">involves what has been called the \u2018sociologist\u2019s fallacy\u2019. This fallacy <\/span><\/p>\n<p><span style=\"color: #800000;\">is seen in full bloom in one sociologist\u2019s criticism of studies of <\/span><\/p>\n<p><span style=\"color: #800000;\">Negro-white IQ differences which equated the groups for SES <\/span><\/p>\n<p><span style=\"color: #800000;\">or other environmental factors: \u2018Actually in most of the studies he <\/span><\/p>\n<p><span style=\"color: #800000;\">[Jensen, 1969a] reports on, the most important environmental <\/span><\/p>\n<p><span style=\"color: #800000;\">variable, the IQ of the parent, has not been equated at all\u2019 <\/span><\/p>\n<p><span style=\"color: #800000;\">(Stinchcombe, 1969, p. 516). Apart from the strictly environmental<\/span><\/p>\n<p><span style=\"color: #800000;\">effect of parental IQ ,1 it is obvious that, since IQ variance contains <\/span><\/p>\n<p><span style=\"color: #800000;\">a large genetic component, equating groups for parental IQ means <\/span><\/p>\n<p><span style=\"color: #800000;\">equating them for genetic factors more than for environmental<\/span><\/p>\n<p><span style=\"color: #800000;\">factors. The same is true, though to a lesser degree, when we <\/span><\/p>\n<p><span style=\"color: #800000;\">equate for SES. When typical Negro children are equated with <\/span><\/p>\n<p><span style=\"color: #800000;\">white children on some index of SES, one is comparing a majority<\/span><\/p>\n<p><span style=\"color: #800000;\">of the Negro population with some lower fraction of the white <\/span><\/p>\n<p><span style=\"color: #800000;\">population.2 The white comparison group, therefore, is not <\/span><\/p>\n<p><span style=\"color: #800000;\">genetically representative of the entire white population but is <\/span><\/p>\n<p><span style=\"color: #800000;\">genotypically (as well as environmentally) lower by some sub\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">stantial degree. Thus, if one supposes one is equating only for <\/span><\/p>\n<p><span style=\"color: #800000;\">environmental influences, equating on SES equates too much.The <\/span><\/p>\n<p><span style=\"color: #800000;\">method would be a proper control of environmental factors if all<\/span><\/p>\n<p><span style=\"color: #800000;\">children had been placed in their SES categories completely at <\/span><\/p>\n<p><span style=\"color: #800000;\">random, in the nature of a true experiment. But as it is, SES <\/span><\/p>\n<p><span style=\"color: #800000;\">classification is more a result than a cause of IQ variance.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>quite possibly the first formulation of the sociologists fallacy.<\/p>\n<p>&nbsp;<\/p>\n<p>&#8211;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #800000;\">Data on two white populations show that fetal loss (Fx genera\u00ad<\/span><\/p>\n<p><span style=\"color: #800000;\">tion) in matings of the parental generation ( P J increases <\/span><\/p>\n<p><span style=\"color: #800000;\">cumulatively by approximately 2-5 percent to 3 percent with <\/span><\/p>\n<p><span style=\"color: #800000;\">each additional country of birth in the great-grandparental <\/span><\/p>\n<p><span style=\"color: #800000;\">generation (Px). A dependent relation shows that increased fetal <\/span><\/p>\n<p><span style=\"color: #800000;\">loss is also related to greater distances between birthplaces of <\/span><\/p>\n<p><span style=\"color: #800000;\">mates within the Px generation. Conversely, low fetal loss is <\/span><\/p>\n<p><span style=\"color: #800000;\">encountered with a small number of countries in the background <\/span><\/p>\n<p><span style=\"color: #800000;\">and shorter distance between birthplaces. It is suggested that a <\/span><\/p>\n<p><span style=\"color: #800000;\">large number of countries of birth represents a larger number <\/span><\/p>\n<p><span style=\"color: #800000;\">of Mendelian gene pools and that with increased mixture of <\/span><\/p>\n<p><span style=\"color: #800000;\">these gene pools, fetal loss increases proportionately. An animal <\/span><\/p>\n<p><span style=\"color: #800000;\">model is cited in support of this contention, (p. 24)<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>Never heard of this effect! It somewhat offsets hybrid vigor.<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>https:\/\/www.goodreads.com\/book\/show\/786753.Educability_And_Group_Differences http:\/\/gen.lib.rus.ec\/book\/index.php?md5=501f355b6e474bdc0b7f3130dc3bf9c0&amp;open=0 &nbsp; Why read a book from 1973? 41 years old? Well, it was a good read indeed! It is interesting how much of the evidence for racial differences were in place already in 1973, and it has more or less only become stronger since then. Basically, the book is a shorter and less [&hellip;]<\/p>\n","protected":false},"author":17,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1839,1653],"tags":[1988],"class_list":["post-4132","post","type-post","status-publish","format-standard","hentry","category-psychometics","category-psychology","tag-jensen","entry"],"_links":{"self":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts\/4132","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/users\/17"}],"replies":[{"embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/comments?post=4132"}],"version-history":[{"count":4,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts\/4132\/revisions"}],"predecessor-version":[{"id":6760,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/posts\/4132\/revisions\/6760"}],"wp:attachment":[{"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/media?parent=4132"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/categories?post=4132"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/emilkirkegaard.dk\/en\/wp-json\/wp\/v2\/tags?post=4132"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}