title: Sex Differences in Detecting Sexual Infidelity : Results of a Maximum Likelihood Method for Analyzing the Sensitivity of Sex Differences to Underreporting.
abstract: Despite the importance of extrapair copulation (EPC) in human evolution, almost nothing is known about the design features of EPC detection mechanisms. We tested for sex differences in EPC inference-making mechanisms in a sample of 203 young couples. Men made more accurate inferences (φmen = 0.66, φwomen = 0.46), and the ratio of positive errors to negative errors was higher for men than for women (1.22 vs. 0.18). Since some may have been reluctant to admit EPC behavior, we modeled how underreporting could have influenced these results. These analyses indicated that it would take highly sex-differentiated levels of underreporting by subjects with trusting partners for there to be no real sex difference. Further analyses indicated that men may be less willing to harbor unresolved suspicions about their partners' EPC behavior, which may explain the sex difference in accuracy. Finally, we estimated that women underreported their own EPC behavior (10%) more than men (0%).
authors.affiliation: Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, P.O. Box 980126, Richmond, VA, 23298-0126, USA. pandrews@vcu.edu.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Andrews
authors.affiliation: Department of Psychology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: Steven W
authors.initials: SW
authors.lastname: Gangestad
authors.affiliation: Department of Psychology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: Geoffrey F
authors.initials: GF
authors.lastname: Miller
authors.affiliation: Communication Studies, University of California, Los Angeles, Los Angeles, CA, USA.
authors.forename: Martie G
authors.initials: MG
authors.lastname: Haselton
authors.affiliation: Department of Biology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: Randy
authors.initials: R
authors.lastname: Thornhill
authors.affiliation: Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, P.O. Box 980126, Richmond, VA, 23298-0126, USA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Neale
keywords: Accuracy; Bias; Error; Evolutionary psychology; Extrapair copulation; Infidelity; Jealousy; Sex differences