„Psychologische Unterschiede zwischen Männern und Frauen“ – Versionsunterschied

Sex and intelligence research investigates differences in the distributions of cognitive skills between men and women. This research employs experimental tests of cognitive ability, which take a variety of forms, including written tests like the SAT. Research focuses on differences in individual skills as well as overall differences in general cognitive ability, which is often called g. IQ tests, specially designed to measure cognitive ability, usually test a variety of skills, and IQ scores are often used as a measure of g.

The populations of men and women differ on average in how well they perform on some of these skill tests, but do equally well on other tests. For example, women tend to score higher on certain verbal and memory tests, whereas men tend to score higher on spatial and mathematical tests. While these results are relatively uncontroversial, the question of whether men and women differ on average in g is a matter of debate among experts. Most recent studies unambiguously find that men as a population are more varied than women in g (i.e. they have a slightly higher variance and therefore there are slighly more men than women at the extremes of ability).

Determining whether men and women differ on average has been more difficult. It is easy to design an IQ test in which either males or females score higher on average, by selecting different tests or giving them different weights, so the question boils down to which weights the different tests should have for the g factor. For example, when the Stanford-Binet test was revised in the 1940's, preliminary tests yielded a slightly higher average IQ for women, a discrepancy attributed to a greater than usual emphasis on verbal ability. The test was subsequently adjusted to give identical averages for men and women.

History

The scientific study of the differences in mental aptitudes between men and women dates back at least as far as the mid-nineteenth century, when the question of women's voting rights arose in a number of countries. In Victorian England, for example, the philosopher John Stuart Mill argued that there were no differences between men and women, whereas the scientist Charles Darwin (in his Descent of Man) argued that women were by their nature inferior in respect to mental ability. Many of these early attempts were based on anecdotal data. However, some scientists, such as Paul Broca (1861), attempted to derive empirical results from various forms of anthropometry, namely the comparison of brain mass.

The findings have provoked controversy at various times, often because political implications were perceived to be attached to them. In the nineteenth century, as noted, whether men and women had equal intelligence was seen by many as a prerequisite for the granting of suffrage. Leta Hollingworth argues that: Women were not permitted to realize their full potential, as they were confined to the roles of child rearing and housekeeping.

With the development of psychology at the end of the nineteenth century, and the evolving focus on intelligence testing in the early twentieth century, further attempts were made by a variety of scientists to examine the mental differences between men and women. British psychologist Cyril Burt proposed in 1912 that there was no sex differences in overall general intelligence, basing his conclusions on the results from a series of reasoning tasks he developed and administered to both boys and girls in various secondary schools in Liverpool.

In the late-twentieth century, whether men and women had different aptitudes is often taken to reveal whether disproportionate employment or payment of men is a form of sexism or simply a reflection of innate aptitudes.

SAT scores

Average SAT scores (recentered) by sex, 1972 - 2003. Source: [1], Table A

The SAT is a voluntary, standardised test taken by many American college applicants. It is administered by the Educational Testing Service, which keeps track of the gender of test-takers and releases SAT scores by gender. In 2001, men scored 533 while women scored 498 overall; men also scored 509 out of 800 on the verbal portion while women scored 502 out of 800. The difference, however, was more pronounced and consistent on the math segment of the SAT. These discrepancies reflect gender differences in scores since the first implementation of the SAT (see table.)

Jackson and Rushton extracted a g factor from 145 items on the 1991 SAT, using responses from 46,509 males and 56,007 females. Their study findings showed that 17- to 18-year old males averaged 3.63 IQ points higher than did their female counterparts, and that the differences become more evident with increasing age. They postulated that this was caused by the relative inactivity of women with advancing age.

Rosser (1989) claimed that there were four potential areas for sex bias through testing:

1. Test questions refer to more men than women, and women are shown in situations of lower status.
2. Test questions refer to contexts more familiar to men.
3. Test validity under-predicts women's academic capabilities and over-predicts men's.
4. Tests that under-predict women's capabilities are used to restrict their educational opportunities.

Following concerns about the persistent gender disparity in SAT scores, a newly-designed SAT was implemented as of 2005 which placed much greater emphasis on writing abilities; areas in which women have historically shown greater strength. The figures in 2006 show an average score of 536 for males and 502 for females in mathematics, 505 for males and 502 for females in critical reading. [2]

As with any standardized test, there will always be general speculation as to the efficiency of the scores in predicting one's cognitive ability to begin with. The most commonly cited discrepancy is the occasional tendency for adept test takers to score very highly, while failing to demonstrate a corresponding high academic aptitude in terms of grading. Conversely, those who fare poorly in standardized testing commonly achieve high marks, evidence which might suggest the prescient purpose of standardized testing is decreasing. An alternative explanation is that the subjective assignment of grades by teachers and professors at secondary and collegiate institutions may itself reflect bias as a subjective process which contrasts with the identity-blind automated process employed by standardized tests such as the SAT.

IQ tests

Recent large representative studies have shown inconsistent results in comparing the overall IQ performances of men and women. Some describe minimal differences, whereas others have demonstrated statistically significant disparities favouring men. What they illustrate consistently, however, is greater variance in the performance of men compared to that of women (ie. men are more represented at the extremes of performance), and that men and women have statistically significant differences in average scores on tests of particular abilities, which even out the overall IQ scores.

Variance in IQ

Hedges and Nowell (1995) performed a meta-analysis of national ability surveys that cover a 32-year period. Their findings suggested significantly greater variance among men compared to women in most abilities.

Deary et al. (2003) performed an analysis of an IQ test administered to almost all children in Scotland at age 11 in 1932 (>80,000). The average IQ scores by sex were 162.69 for girls and 163.36 for boys. The difference in mean IQ was not significant. However, the standard deviation was 14.1 for girls and 14.9 for boys. This difference was statistically significant. In the sample studied, 49.6% are girls and 50.4% are boys. Because of the difference in variance between the sexes, however, girls are in excess by 2% in the middle IQ range of 90–115. At the extreme IQ ranges, 50–60 and 130–140, boys make up 58.6% and 57.7% of the population (gaps of 17.2% and 15.4%) respectively. That is, boys were overrepresented amongst the lowest and highest IQ groups. It is generally observed that males tend to hit the most positive and negative performance results of many tests.

An extensive study published by the British Journal of Psychology in 2005 used research based on IQ tests given to 80,000 people and a further study of 20,000 students. It demonstrated that men on average scored five points ahead on IQ tests, a difference which remained statistically significant despite the study design accommodating for gender-specific abilities. The study also found a much higher proportion of men in the higher IQ brackets. "There are 3 men to each woman with an IQ above 130 and 5.5 men for each woman with an IQ above 145" according to Dr Paul Irwing, the paper's lead researcher. He goes on to say: "These different proportions of men and women with high IQ scores may go some way to explaining the greater numbers of men achieving distinctions of various kinds, such as chess grandmasters, Fields medallists for mathematics, Nobel prizewinners and the like."

Consistent with this finding, men have been shown to predominate in many high IQ societies. In Mensa the male-to-female ratio is 3:2, based on US demographics in 2008. [3]

Specific abilities

• Verbal/mathematical ability: Hedges and Nowell (1995) demonstrated strong average advantages for men in math and science and typically male vocations, and moderate to strong average advantages to women in reading. This trend was also found in a 2001 report by Richard J. Cooley of the ETS.
• Spatial tasks/memory: Men have been shown to outperform women in abilities that require spatial awareness such as navigation, map reading and target-directed motor skills, whereas women show greater proficiency and reliance on landmarking for memory skills.
• General knowledge: A study by Richard Lynn showed that men show greater ability than women in maintaining broad general knowledge
• Education: In the United States and Great Britain, women outnumber men at colleges and universities, except at technical institutions which emphasise mathematics and science such as MIT and Caltech, where men predominate. An analysis of 2007 figures by Universities UK showed that, even given this overall imbalance, men continue to achieve a significantly greater proportion of first class degrees.
• Academia: Men outnumber women in tenured faculty positions in mathematics and science, and women outnumber men in tenured faculty positions in humanities fields.Vorlage:Fact

Controversy

Another study performed by the American Psychological Association in response to the book The Bell Curve, which investigated the difference in intelligence between different social classes (strongly correlated with race in the U.S.), determined (as did the authors of the book) that the studies available in 1995 showed no major difference between males and females in regard to IQ scores.

In July 2006, Stanford University neurobiologist Ben Barres, a transsexual man, wrote a provocative piece in Nature on his own experiences as both a male and female scientist. Barres argued that prior to transition, he had succeeded as a female despite pervasive sexism. Barres wrote that numerous studies show female scientists are consistently rated lower than their male counterparts with the same levels of productivity and credentials.

It is possible that sexual dimorphism may exist in regard to intellectual abilities in humans. Men may have evolved greater spatial abilities, possibly as a result of certain behaviors, such as navigating during a hunt, that they were more likely to be involved in during humans' evolutionary history. Similarly, women may have evolved to devote more mental resources to gathering food, as well as understanding and tracking relationships and reading others' emotional states in order for them to be able to better understand their social situation.

Another possibility is the effects of socialization. Girls are sometimes discouraged from studying math or science. Similarly, boys are sometimes discouraged from displaying empathy, or from spending excessive time reading for pleasureVorlage:Fact.

According to Diane F. Halpern, the above two hypotheses are not mutually exclusive; some combination of the two may be at work. She wrote in the preface of her 2000 book Sex Differences In Cognitive Abilities: Vorlage:Cquote

See also

• Race and intelligence
• Sex and crime
• Ruth Hubbard

Bibliography

• Born, M. P., Bleichrodt, N. & van der Flier, H.: Cross-cultural comparison of sex-related differences on intelligence tests. In: Journal of Cross-Cultural Psychology. 18. Jahrgang, 1987, S. 283–314. 
• Haier RJ, Benbow CP.: Sex differences and lateralization in temporal lobe glucose metabolism during mathematical reasoning. In: Dev Neuropsychol. 11. Jahrgang, 1995, S. 405–414. 
• Lynn, Richard, with P.Irwing and T.Cammock: Sex differences in general knowledge. In: Intelligence. 30. Jahrgang, 2002, S. 27–40. 
• Lynn, Richard: Sex differences in intelligence and brain size: a developmental theory. In: Intelligence. 27. Jahrgang, 1999, S. 1–12.