The Distance Between Mars and Venus: Measuring Global Sex Differences in Personality

[FarCenter]

Abstract

Background
Sex differences in personality are believed to be comparatively small. However, research in this area has suffered from significant methodological limitations. We advance a set of guidelines for overcoming those limitations: (a) measure personality with a higher resolution than that afforded by the Big Five; (b) estimate sex differences on latent factors; and (c) assess global sex differences with multivariate effect sizes. We then apply these guidelines to a large, representative adult sample, and obtain what is presently the best estimate of global sex differences in personality.

Methodology/Principal Findings
Personality measures were obtained from a large US sample (N = 10,261) with the 16PF Questionnaire. Multigroup latent variable modeling was used to estimate sex differences on individual personality dimensions, which were then aggregated to yield a multivariate effect size (Mahalanobis D). We found a global effect size D = 2.71, corresponding to an overlap of only 10% between the male and female distributions. Even excluding the factor showing the largest univariate ES, the global effect size was D = 1.71 (24% overlap). These are extremely large differences by psychological standards.

Significance
The idea that there are only minor differences between the personality profiles of males and females should be rejected as based on inadequate methodology.

Marco Del Giudice1*, Tom Booth2, Paul Irwing2

1 Department of Psychology, University of Turin, Torino, Italy, 2 Manchester Business School, University of Manchester, Manchester, United Kingdom

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0029265

[randome]

1. A lot of gobble-de-goop.

Is this about sex or gender? I can't tell.

[FarCenter]

5. I think it is about sex

The data set used indicates the sex of each subject.

It would be interesting to do the clustering analysis on a data set with subjects identified by the eight sex/gender combinations.

[lumberjack_jeff]

2. Finding the bottom line in this paper is like spelunking.

Nevertheless, here it is;

Conclusion

In conclusion, we believe we made it clear [font color="red"](HA!)[/font] that the true extent of sex differences in human personality has been consistently underestimated. While our current estimate represents a substantial improvement on the existing literature, we urge researchers to replicate this type of analysis with other datasets and different personality measures. An especially critical task will be to compare self-reported personality with observer ratings and other, more objective evaluation methods. Of course, the methodological guidelines presented in this paper can and should be applied to domains of individual differences other than personality, including vocational interests, cognitive abilities, creativity, and so forth. Moreover, the pattern of global sex differences in these domains may help elucidate the meaning and generality of the broad dimension of individual differences known as “masculinity-femininity” [11]. In this way, it will be possible to build a solid foundation for the scientific study of psychological sex differences and their biological and cultural origins.

The funny thing about contemporary conventional wisdom, is that its purpose is to discriminate ourselves from what we consider antiquated ideas.

Often the antiquated ideas are not as flawed as we consider them to be.

[MineralMan]

19. Well, I can find my bottom with both hands.

[slackmaster]

3. I have to laugh at an author who puts the first sentence of an abstract in passive voice

[antigone382]

4. This goes against a much larger and more established body of research...

...and it does not appear to be derived from a random sample--but rather one "structured" to be demographically similar to the United States population. Random sampling is critical to valid quantitative research, as the entire foundation of probability theory on which statistical analysis is based depends upon a random sample. In addition, the principle question is not whether observable psychological differences between men and women exist--no one would claim that. The issue is to what extent those differences are the result of biology or environment (or, as is almost obviously the case, an enormously complicated combination of the two). No self-reported personality survey is going to tell you that, no matter how sophisticated your statistical analysis.

[FarCenter]

13. In many cases it doesn't matter whether the differences are the result of biology or environment

Although environmentally caused differences can theoretically be changed by changing the environment, cultural, economic, political, religious and other factors are relatively hard to change on less than a multi-generational time scale.

Whatever the existing differences are for a given cohort, e.g. the eligible voters in the US, they will not change significantly for one or two election cycles. Political advertising must take them as a given.

Culturally determined differences are almost as hard to change as biologically caused ones.

[seabeyond]

16. 1950's women were thought to be biologically less capable, smart, independent. in a mere 4 decades

we see the myth, the fable of that conclusion. all due to environmental conditioning.

same could be said with sex..... women have to have an emotional attachment. oh wait.... not really. though we arent finished busting that bubble cause too many dont want to consider otherwise.

males more visual, nope... not true wither

[chrisa]

6. I clicked on this thread thinking that this was a load of crap.

My opinion didn't change.

[redqueen]

7. Socialization doesn't exist or have measuable effects

is that what these guys think?

What a waste of time.

[seabeyond]

9. which is more power, zillion of years ago or cultural conditioning since birth. dont factor that in

it is garbage.

[RadiationTherapy]

11. Is this paper saying we are natured or nurtured differently?

Without distinguishing between the two, there is nothing here to dispute the idea that sex and gender are connected via nurturing and have little to do with biological inheritance.

[marions ghost]

12. So let them go ahead with this line of investigation

--others will have fun debunking it.

My gut tells me that while there are differences between males and females psychologically, it's not huge.

If you let kids develop without strict gender role expectations, you can easily see this, no matter how many times dolls are chosen over trucks. Parents who teach their daughters and sons both --how to use hammers, tend to cars AND do laundry and cook--check in here.

If we could BE what we want to be in this society, personality types would transcend gender.

[RadiationTherapy]

14. Check.

I am raising my daughter to know how to take care of herself, how to find information to help herself, and how to ask others for help.

[seabeyond]

15. i was raised as a person, and had the same expectations as brothers.

i raise my boys as people and allow them to find their own authentic masculinity as i was allowed to with my femininity. no greater gift a parent can allow their child.

[RadiationTherapy]

18. We cannot prepare them with every skill and need, but they ought to feel they have PERMISSION

to work hard at anything.

[Spike89]

17. Way more complex than this study can cope with

There probably are many fewer differences between male and female children than you'll find between male and female adults (not to mention teenagers as they learn to cope with the distinctly different hormone cocktails). Anyone who doesn't believe testosterone (as just one example) is a powerful mood and behavioral influence simply has never been or been around someone dealing with low/high testosterone.
Even so, cultural influences are incredibly strong and virtually impossible to separate because they often reinforce the slight physiological differences. Are men more aggressive because they have more testosterone, or because exibiting aggression is rewarded as "manly behavior"? The answer is obviously yes to both, but which is more powerful and can you make any meaningful conclusions when each subject has a slightly different metabolism and of course experiences that are unique to them?
Studies such as this are fine and interesting, but they simply can't be used to determine much if anything about why females and males sometimes seem like aliens to each other.

[lumberjack_jeff]

20. Here's the interesting thing.

Why do we assume that grade school teachers (90% of whom are women) allow kids to develop without strict gender role expectations? The basic educational frame is that the way women are raised is the norm to which everyone should comply.

I think it's more plausible that school attempt to make kids develop with the gender role expectations that teachers were raised with.

Boys don't have to be boys. If you try hard enough you can turn them into self-loathing and maladapted men.