Race & QI : retard mental

Le retard mental, ou handicap mental, est un trouble généralisé qui se caractérise par un dysfonctionnement cognitif. Les individus frappés de retard mental ont un QI inférieur à 70. Entre 50 et 70, on parlera d’un retard mental léger. En dessous de 50, on parlera d’un retard mental modéré.

Les races diffèrent en termes de QI (70 pour les africains sub-sahariens, 85 pour les afro-américains, 100 pour les blancs) mais également dans la prévalence du retard mental.

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Les conséquences et coûts sociaux de la pornographie

Aujourd’hui plus que jamais, la pornographie est consommée en une quantité de plus en plus grande. La faute à la pornographie en ligne, accessible et anonyme. Les conséquences sociales deviennent une préoccupation. C’est exactement le sujet dont il est question dans le livre de Mary Eberstadt et Mary Anne Layden (2010) intitulé “The Social Costs of Pornography”.

L’ouvrage est un condensé d’études, de témoignages et d’observations faites par des cliniciens et psychologues. Bien que les recherches en ce domaine particulier ne sont pas toujours claires, les auteurs présentent une liste des découvertes dont elles sont presque certaines qu’elles ne souffrent d’aucun doute.

Pamela Paul (p. 13), une journaliste du TIME Magazine est régulièrement citée par les auteurs. Dans son livre “Pornified” (2005), Pamela écrit :

Aujourd’hui, le nombre de gens qui regardent la pornographie est stupéfiant. Les américains louent plus de 800 millions de vidéos et DVDs pornographiques (environ un cinquième de tous les films loués est pornographique), et les 11 000 films porno tournés chaque année dépassent de loin la liste annuelle de 400 de Hollywood. Quatre milliards de dollars par an sont consacrés à la vidéo pornographique aux États-Unis, plus que le football, le baseball et le basketball. Un internaute sur quatre regarde un site pornographique à un mois donné. Les hommes regardent de la pornographie en ligne plus qu’ils ne regardent tout autre sujet. Et 66% des hommes de 18 à 34 ans visitent un site pornographique chaque mois.

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Dissecting practical intelligence theory: Its claims and evidence

Dissecting practical intelligence theory: Its claims and evidence

Linda S. Gottfredson 2003


Sternberg et al. [Sternberg, R. J., Forsythe, G. B., Hedlund, J., Horvath, J. A., Wagner, R. K., Williams, W. M., Snook, S. A., Grigorenko, E. L. (2000). Practical intelligence in everyday life. New York: Cambridge University Press] review the theoretical and empirical supports for their bold claim that there exists a general factor of practical intelligence that is distinct from ‘‘academic intelligence’’ ( g) and which predicts future success as well as g, if not better. The evidence collapses, however, upon close examination. Their two key theoretical propositions are made plausible only by ignoring the considerable evidence contradicting them. Their six key empirical claims rest primarily on the illusion of evidence, which is enhanced by the selective reporting of results. Their small set of usually poorly documented studies on the correlates of tacit knowledge (the ‘‘important aspect of practical intelligence’’) in five occupations cannot, whatever the results, do what the work is said to have done — dethroned g as the only highly general mental ability or intelligence.

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On Sternberg’s ‘Reply to Gottfredson’

On Sternberg’s ‘‘Reply to Gottfredson’’

Linda S. Gottfredson

Intelligence 31 (2003) 415–424


Sternberg disputes not a single point in my critique of his work on practical intelligence. Instead, he discusses his broader theory of successful intelligence and answers self-posed objections from unspecified critics. His discussion exhibits the same problematic mode of argument and use of evidence that my critique had documented: it repeats the unsubstantiated claims that critics question as if merely repeating them somehow rebutted the critics; it ridicules rather than answers critics while claiming to do the reverse; and it spuriously validates Sternberg’s theory by reporting evidence selectively and inaccurately.

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Hülsmann on the Economics of Deflation

The Ethics of Money Production
by Jörg Guido Hülsmann

Chapter 3: Money within the Market Process


This way of presenting things is not fully correct. It is true that an increased money supply tends to bring about higher money prices, and thus diminishes the purchasing power of each unit of money. But it is not true that this process necessarily operates in favor of the debtor and to the detriment of the creditor. A creditor may not be harmed at all by a 25 percent decrease in the purchasing power of money if he has anticipated this event at the point of time when he lent the money. Suppose he wished to obtain a return of 5 percent on the capital he lent, and that he anticipated the 25 percent depreciation of the purchasing power; then he would be willing to lend his money only for 30 percent, so as to compensate him for the loss of purchasing power. In economics, this compensation is called “price premium” — meaning a premium being paid on top of the “pure” interest rate for the anticipated increase of money prices. This is exactly what can be observed at those times and places where money depreciation is very high. 3

3 Late scholastic Martín de Azpilcueta argued that price premiums were not per se usurious, but legitimate compensations for loss of value. See Martín de Azpilcueta, “Commentary on the Resolution of Money,” Journal of Markets and Morality 7, no. 1 (2004) §48–50, pp. 80–83.

A creditor might actually benefit from lending money even though the purchasing power declines. In our above example, this would be so if the depreciation turned out to be 15 percent, rather than the 25 percent he had expected. In this case, the 30 percent interest he is being paid by his debtor contains three components: (1) a 5 percent pure interest rate, (2) a 15 percent price premium that compensates him for the depreciation, and (3) a 10 percent “profit.”

The same observations can be made, mutatis mutandis, for the debtors. They do not necessarily benefit from a depreciating purchasing power of money, and they can even earn a “profit” when money’s purchasing power increases if the increase turns out to be less than that on which the contractual interest rate was based. It all depends on the correctness of their expectations.

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The Myth of ‘Involuntary Unemployment’

Since layoff is necessary to allow obsolete firms to decline or disappear in favor of new firms that tend to conform to the changes of individual preferences, a frictional unemployment emerges.

Obviously, unemployment caused by regulations (e.g., minimum wage, unemployment benefits, labor unions) is considered as involuntary unemployment. Economists do not deny this. But some still subscribe to the idea that frictional unemployment could be labelled involuntary unemployment as well.

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Coming Apart, by Charles Murray

Coming Apart: The State of White America, 1960-2010

Charles Murray (2012)

Chapter 2 – The Foundations of the New Upper Class

The Enabler: Wealth

Coming Apart p. 049

The poor didn’t actually get poorer – the growth of in-kind benefits and earned-income tax credits more than made up the drop in pretax cash income – but they didn’t improve their position much either. 5

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Income Inequality and IQ, by Charles Murray

Income Inequality and IQ

Charles Murray (1998)


This study is one of a series commissioned by the American Enterprise Institute on trends in the level and distribution of U.S. wages, income, wealth, consumption, and other measures of material welfare. The issues addressed in the series involve much more than dry statistics: they touch on fundamental aspirations of the American people – material progress, widely shared prosperity, and just reward for individual effort – and affect popular understanding of the successes and shortcomings of the private market economy and of particular government policies. For these reasons, discussions of “economic inequality” in the media and political debate are often partial and partisan as well as superficial. The AEI series is intended to improve the public discussion by bringing new data to light, exploring the strengths and weaknesses of various measures of economic welfare, and highlighting important questions of interpretation, causation, and consequence.

Each study in the series is presented and discussed in draft form at an AEI seminar prior to publication by the AEI Press. Marvin Kosters, director of economic policy studies at AEI, organized the series and moderated the seminars. A current list of published studies appears on the last page.

Christopher DeMuth
President, American Enterprise Institute

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Effect of breast feeding on intelligence in children: prospective study, sibling pairs analysis, and meta-analysis

Effect of breast feeding on intelligence in children: prospective study, sibling pairs analysis, and meta-analysis

Geoff Der, G David Batty, Ian J Deary, 2006.


Objective. To assess the importance of maternal intelligence, and the effect of controlling for it and other important confounders, in the link between breast feeding and children’s intelligence.

Design. Examination of the effect of breast feeding on cognitive ability and the impact of a range of potential confounders, in particular maternal IQ, within a national database. Additional analyses compared pairs of siblings from the sample who were and were not breast fed. The results are considered in the context of other studies that have also controlled for parental intelligence via meta-analysis.

Setting. 1979 US national longitudinal survey of youth.

Subjects. Data on 5475 children, the offspring of 3161 mothers in the longitudinal survey.

Main outcome measure. IQ in children measured by Peabody individual achievement test.

Results. The mother’s IQ was more highly predictive of breastfeeding status than were her race, education, age, poverty status, smoking, the home environment, or the child’s birth weight or birth order. One standard deviation advantage in maternal IQ more than doubled the odds of breast feeding. Before adjustment, breast feeding was associated with an increase of around 4 points in mental ability. Adjustment for maternal intelligence accounted for most of this effect. When fully adjusted for a range of relevant confounders, the effect was small (0.52) and non-significant (95% confidence interval -0.19 to 1.23). The results of the sibling comparisons and meta-analysis corroborated these findings.

Conclusions. Breast feeding has little or no effect on intelligence in children. While breast feeding has many advantages for the child and mother, enhancement of the child’s intelligence is unlikely to be among them.

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