Males have greater G: sex differences in general mental ability

Discussion in 'Politics & Religion' started by Rick_Michael, Sep 9, 2006.

  1. #1
    http://www.eurekalert.org/pub_releases/2006-09/uowo-mhg090506.php



    A study of 100,000 17- to 18-year-olds on the SAT

    [​IMG]

    A study of 100,000 17- to 18-year-olds on the Scholastic Assessment Test published in the September 2006 issue of the journal Intelligence, has confirmed a surprising new finding-that men have a 4- to 5-point IQ advantage over women by adulthood. Because girls mature faster than boys, the sex difference is masked during the school years, which explains why the sex difference was missed for 100 years.

    A study published in the September 2006 issue of the journal Intelligence analyzed 145 items from the Scholastic Assessment Test (SAT) in 100,000 17- to 18-year-olds and found a male IQ advantage of 3.63 points.

    It also found that the g factor--the general factor of mental ability underlay both the SAT Verbal (SAT-V) and the SAT Mathematics (SAT-M) scales with the congruence between these components greater than 0.90, and that it was the g factor that predicted student grades better than the traditionally used SAT-V and SAT-M scales.

    The male and the female g factors were congruent in excess of .99, and they favored males to an equivalent of 3.63 IQ points.

    The male-female differences were present at every socioeconomic level, and across several ethnic groups.

    The average male advantage was found "throughout the entire distribution of scores, in every level of family income, for every level of fathers' and of mothers' education, and for each and every one of seven ethnic groups," said J. Philippe Rushton, professor of psychology at the University of Western Ontario, one of the authors of the study.

    The paper's results dovetail with those from several other recently published studies showing that men--surprisingly--have a 4- to 5- IQ point advantage over women by late adolescence and early adulthood. Before that age the two sexes are equal in general intelligence.

    As such, the findings overturn a 100 year consensus that men and women average the same in general mental ability.

    Because girls mature faster than boys, the sex difference is masked during the school years. Since almost all the data showing an absence of sex differences were gathered on school children, this might explain why the sex difference was missed for so long.

    For decades, however, psychologists have accepted that men and women differ in their test "profiles," with males averaging higher on tests of "spatial ability" and females higher on tests of "verbal ability." These differences were assumed to average out.

    The authors of the study, psychologists Douglas N. Jackson and J. Philippe Rushton at the University of Western Ontario, conducted the study because two recent sets of observations had raised anew the question of sex differences in general intelligence.

    The first was that the general factor of mental ability--g--was found to permeate all tests to a greater or lesser extent. Thus, a "spatial" test may be relatively high on g (mental rotation) or low (perceptual speed), a "verbal" test may be relatively high (reasoning) or low (fluency), as may a "memory" test be high (repeating a series in reverse order) or low (repeating a series in presented order).

    More than any other factor, the test's g loading best determines a test's power to predict academic achievement, creativity, career potential, and job performance. Hence, the question of sex differences became formulated more precisely as: "Are there sex differences on the g factor?"

    Another set of observations concerned the sex difference found in brain size and the relation between brain size and cognitive ability. Studies published in 1992 at the University of Western Ontario by zoologist C. Davison Ankney, and also by psychologist Rushton, showed men average a 100-gram advantage over women in brain weight (and volume).

    A 1997 study in Denmark documented that men have 15% more neurons than women (22.8 versus 19.3 billion).

    Over two-dozen Magnetic Resonance Imaging studies have confirmed a brain-size/IQ correlation of about 0.40. So, if males average a larger brain, shouldn't they also average a higher IQ score?

    British psychologist Richard Lynn at the University of Ulster in Northern Ireland, and Paul Irwing at the University of Manchester found that adult men consistently average 4 to 5 IQ points higher than adult women in a series of recent large-scale studies using a number of intelligence tests in various countries. (Irwing & Lynn's most recent paper appeared in Nature on July 6, 2006.)

    Other researchers too have found a male advantage in general mental ability, including Prof. Helmuth Nyborg at the University of Aarhus in Denmark, who earlier this year was disciplined by his university for talking to the media about his "politically incorrect" conclusions.

    Prof. Rushton agreed that "these are unpopular conclusions." He said, "only more data can determine the true nature of sex differences in cognitive ability. However, people should not be made to feel afraid to study controversial issues."

    Prof. Rushton accepted that sex differences in general mental ability could help explain the "glass ceiling" phenomenon.

    But he also noted the paradox that although men may have higher IQ scores, women do increasingly well in school exams.

    It will be very hard to argue that selection bias caused the sex difference in this data set, the authors wrote. "That would require the assumption that there are hypothetical respondents who, if tested, would provide a compensating female-male advantage in g that would counterbalance the findings. They would have to be found at every level of SAT performance, in every level of family income, for every level of fathers' and of mothers' education, and for every ethnic group examined."
    ###

    Corresponding author: J. Philippe Rushton, Department of Psychology, University of Western Ontario, London, Ontario, N6A 5C2, Canada Email: Tel: 519-661-3685

    On the Web: Article pdf: http://www.ssc.uwo.ca/psychology/faculty/rushton_pubs.htm

    Full Citation: Jackson, D. N., & Rushton, J. P. (2006). Males have greater g: Sex differences in general mental ability from 100,000 17- to 18-year-olds on the Scholastic Assessment Test. Intelligence, 34, 479-486.
     
    Rick_Michael, Sep 9, 2006 IP
  2. northpointaiki

    northpointaiki Guest

    Messages:
    6,876
    Likes Received:
    187
    Best Answers:
    0
    Trophy Points:
    0
    #2
    I'd be curious to see a comparison of means test.
     
    northpointaiki, Sep 10, 2006 IP
  3. mr_unknown

    mr_unknown Peon

    Messages:
    27
    Likes Received:
    1
    Best Answers:
    0
    Trophy Points:
    0
    #3
    i think its cbvious without this research that males are much smarter but in this world u must have a prove to talk and here is the prove GIRLS !!!!!!! ;)
     
    mr_unknown, Sep 10, 2006 IP
  4. jaybong

    jaybong Peon

    Messages:
    630
    Likes Received:
    44
    Best Answers:
    0
    Trophy Points:
    0
    #4
    jaybong, Sep 10, 2006 IP
  5. Rick_Michael

    Rick_Michael Peon

    Messages:
    2,744
    Likes Received:
    41
    Best Answers:
    0
    Trophy Points:
    0
    #5
    There's quite a bit of info at his site....

    http://www.ssc.uwo.ca/psychology/faculty/rushton_pubs.htm

    This guy doesn't shy away from controversy...

    Quote from his site:

    'More controversial is my work on race differences. In new studies and reviews of the world literature, I consistently find that East Asians and their descendants average a larger brain size, greater intelligence, more sexual restraint, slower rates of maturation, and greater law abidingness and social organization than do Europeans and their descendants who average higher scores on these dimensions than do Africans and their descendants. To explain this pattern I proposed a gene-based evolutionary theory. My book, Race, Evolution, and Behavior reviews the theory and many of the data sets.'
     
    Rick_Michael, Sep 10, 2006 IP
  6. Dead Corn

    Dead Corn Peon

    Messages:
    1,072
    Likes Received:
    21
    Best Answers:
    0
    Trophy Points:
    0
    #6
    Then why is everyone so dumb?
     
    Dead Corn, Sep 10, 2006 IP