Avoir des enfants rend-il heureux ?

Kanazawa (2004) avait démontré qu’avoir des enfants ne rendait pas les parents plus heureux. La parentalité diminue en fait le bonheur. En utilisant les données du General Social Survey, il montre que la parentalité a un effet négatif sur le bonheur (variable dépendante) mais que le fait d’être marié était associé à un bonheur plus élevé. Je vais ici tenter de répliquer ce résultat. Ensuite, je commenterais l’étude de Myrskylä & Margolis (2012) dont la conclusion des auteurs diffère de la mienne. Enfin, j’expliquerai que ces mesures du “bonheur général” ne sont pas des évaluations adéquates du bonheur.

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The Social Costs of Pornography


A Statement of Findings and Recommendations

Mary Eberstadt and Mary Anne Layden, 2010.


SINCE THE BEGINNING OF THE INTERNET AGE, pornography has been consumed in greater quantities than ever before in human history, and its content has grown more graphic. Recent research suggests that pornography consumption — especially consumption of a more hard-core or violent sort — has negative effects on individuals and society. More studies are necessary, but a growing body of research strongly suggests that for some users pornography can be psychologically addictive, and can negatively affect the quality of interpersonal relationships, sexual health and performance, and social expectations about sexual behavior. Widespread pornography consumption appears to pose a serious challenge to public health and to personal and familial well-being. With concerted action from legislators, the therapeutic community, educators, policymakers, and responsible corporate leaders, however, some of the negative effects of pornography consumption can be combated.

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The Bell Curve: Intelligence and Class Structure in American Life, With a New Afterword by Charles Murray

The Bell Curve: Intelligence and Class Structure in American Life, With a New Afterword by Charles Murray

Herrnstein Richard J., and Murray Charles, 1994

Chapter 3 : The Economic Pressure to Partition

SPECIFICS SKILLS VERSUS G IN THE MILITARY … What explains how well they performed? For every one of the eighty-nine military schools, the answer was g – Charles Spearman’s general – intelligence. The correlations between g alone and military school grade ranged from an almost unbelievably high .90 for the course for a technical job in avionics repair down to .41 for that for a low-skill job associated with jet engine maintenance. [25] Most of the correlations were above .7. Overall, g accounted for almost 60 percent of the observed variation in school grades in the average military course, once the results were corrected for range restriction (the accompanying note spells out what it means to “account for 60 percent of the observed variation”). [26]

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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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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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The Savanna Principle

The Savanna Principle

Satoshi Kanazawa
Manage. Decis. Econ. 25: 41–54 (2004)


For instance, one of the entities that we know for sure did not exist in the EEA is television. The fundamental principles of EP would therefore imply that humans have difficulty recognizing and dealing with TV. This indeed appears to be the case. People who watch certain types of TV shows are more satisfied with their friendships, just like they are if they have more friends or spend more time socializing with them in real life. It appears that the human brain has difficulty distinguishing between real friends and imaginary ones they see on TV, because it did not exist in the EEA (Kanazawa, 2002). It is this fundamental observation, that our brain and its psychological mechanisms are strongly biased to view and respond to the environment as if it were still the EEA, which leads to the Savanna Principle.

It is true, as critics of EP often point out, that the EEA, tens of thousands of years past, is not directly observable. We can make inferences about it, based both on archeological records and ethnography of contemporary hunter-gatherer societies, but it is unlikely that we will ever know all the details of the EEA. It is therefore impossible for us to draw all the implications of the above observation for our current social behavior. However, there are certain things about our ancestral life in the EEA that we know reasonably well. We know that our ancestors lived in small bands not exceeding 200 individuals; they did not live in a metropolis where everybody can be anonymous. We know that all communications between people in the EEA were direct and face-to-face; they did not have telephones, computers or even writing that allowed them to communicate without facing each other. It is my suggestion in this paper that these few facts that we know about the EEA are sufficient to use the Savanna Principle to figure out which hypotheses about human behavior are likely to fail and why.

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De Gustibus Est Disputandum

De Gustibus Est Disputandum

SATOSHI KANAZAWA, Indiana University of Pennsylvania, 2001.

Principles of Evolutionary Psychology

Our preference for sweets and fats is an example of an evolved psychological mechanism (Barash 1982:144-47). Throughout most of human evolutionary history, procurement of sufficient calories to sustain our bodies physically was a particularly severe problem of adaptation (survival); malnutrition was a common problem. In this environment, those who had a “taste” for sweets and fats (which have higher calories) were better off physically than those who did not have the same taste. Those who had this taste therefore lived longer, led healthier lives and produced higher-quality offspring than those who didn’t. They in turn passed on their taste to their offspring, over many thousands of generations, until most of us living today have a strong preference for sweets and fats. (See Buss 1995:5-9 for other examples of evolved psychological mechanisms.)

Note that we do not consciously choose or decide to like sweets and fats. We just like them but otherwise don’t know why; sweet and fatty foods just taste good to us. [...]

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Social sciences are branches of biology

Social sciences are branches of biology

Satoshi Kanazawa, 2004.

3. Puzzles: wage penalty for motherhood, wage reward for fatherhood (and bigger reward from boys than girls)

In a recent study, Budig and England (2001) find that mothers earn less than non-mothers with similar characteristics. The negative effect of motherhood on wage is greater for married mothers than for unmarried mothers. Their finding is in stark contrast to Lundberg and Rose’s (2000) discovery that fathers earn more than non-fathers with similar characteristics. In other words, there appears to be a wage penalty for motherhood and a wage reward for fatherhood.

Both Budig and England (2001) and Lundberg and Rose (2000) use a statistical technique called the fixed-effect model. By using two data points for each individual, before and after parenthood, the fixed-effect model controls for all unobserved heterogeneity, and allows these authors to rule out the possibility of selection bias. In other words, Budig and England (2001) demonstrate that it is not because women with lower earning capacities are more likely to become mothers that mothers earn less than non-mothers, and Lundberg and Rose (2000) demonstrate that it is not because men with higher earning capacities are more likely to become fathers that fathers earn more than non-fathers. It is motherhood itself that reduces wages, and it is fatherhood itself that increases them.

Further, Lundberg and Rose (2002) find, once again using the fixed-effect model, that such ‘wage reward’ for fatherhood is greater if the men have boys than if they have girls. Men earn more, and work longer hours, in response to the birth of sons than to that of daughters. What accounts for these peculiar patterns? What explains the puzzling fact that motherhood carries a wage penalty but fatherhood carries a wage reward, and that such wage reward for fatherhood is greater if the men have sons than if they have daughters?

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