“At the Interface of Social Cognition and Psychometrics: Manipulating the Sex of the Reference Class Modulates Sex Differences in Personality Traits”, Aaron W. Lukaszewski, James R. Roney, Michael E. Mills, Larry C. Bernard2013-12 ()⁠:

Psychometric surveys suggest that sex differences in personality are minimal. Herein, we argue that (1) the mind is likely biased toward assessing oneself relative to same-sex others, and (2) this bias may affect the measurement of sex differences in personality.

In support of this, an experiment [n = 149 undergraduates] demonstrates modulation of sex differences on the HEXACO facets by manipulating the sex of the “reference class”—the group of people subjects compare themselves to when making self-assessments on survey items.

Although patterns varied across traits, sex differences were relatively small in the “unspecified” and “same-sex” reference class conditions—but substantially larger in the “opposite-sex” condition.

These findings point to a same-sex comparison bias that may impact the measurement of sex differences in personality.

[Keywords: gender differences, HEXACO, personality, personality assessment, psychometrics, sex differences, social cognition]