Another day, another debate over how different men and women are, psychologically speaking. Bobbi Carothers and Harry Reis argue that Men and Women Are From Earth.
Their approach is rather interesting.
We sought to empirically determine whether standard gender differences are better conceived as taxonic or dimensional. Although men and women may differ on average in myriad ways, these differences may be dimensional, reflecting different amounts of a given attribute assessed along a single dimension, or qualitative, sorted into fundamentally distinct categories... this difference has considerable importance for understanding the fundamental nature of gender differences.
Using lots of previously published data (13,000 people) and subjecting it to three different methods of statistical "taxometric analysis", they claim that on most psychological measures, there's no evidence that the two sexes are qualitatively different. This is on things like sexual attitudes, personality, and interest in science according to self-report questionnaires.
They give the following hypothetical example to illustrate the idea (my picture based on theirs)
Men are taller than women and also have shorter hair. If you plot a scatterplot of height vs hair length including both genders, you find a negative correlation. However, there is no such correlation within each gender. So gender is a taxon - in this case. There is something qualitatively different between men and women here.
Their argument is that psychological differences between the genders are, in most cases, not because "male" and "female" are two distinct taxons.
So what? I previously covered a paper called The Distance Between Mars and Venus claiming that the difference between men and women on average are larger than previously thought, if you look at all the differences taken together. That's actually consistent with what Carothers and Reis are saying, I think, because it assumes that each of the differences is dimensional and quantitative.
In other words, maybe sexes differ only by a matter of degree, albeit by a larger degree than you'd think at first glance.
All of this leaves open the question of
why
they differ on average, though. According to yet another study just out, the size of the gap is correlated with the amount of gender inequality in different countries. Women from places where they have much lower incomes, career prospects, etc. compared to men, also endorse more 'feminine' traits.
Personally I consider the question of gender differences largely open because I'm skeptical of self-report questionnaire measures in psychology; objective measures of actual behaviour, stuff like crime statistics, seems to me more interesting.
The fact that the great majority of sex offenders are male, for example, must mean something; I'm not sure what, but I don't think questionnaires will help us find out...
Carothers, B., and Reis, H. (2012). Men and Women Are From Earth: Examining the Latent Structure of Gender. Journal of Personality and Social Psychology DOI: 10.1037/a0030437