I am going to put forth a different theory, at least with respect to the openness to new experiences portion. Openness makes a woman a highly desirable mate because it is at the core of the definition of "femininity." As such, women who are polarized in a highly feminine direction will tend to attract highly "masculine" men. So rather than attracting other men with high "openness" ratings, they are attracting men with high "masculinity" ratings, which is not being quantified on this chart, although I think that agreeableness probably works as a very good inversely correlated metric.

In any case, masculine men are the ones that have the most options because women are attracted to this trait first and foremost. I am positing that the primary bottleneck in terms of men cheating on women is options, it has very little to do with anything about the woman being cheated on. I put forth all professional athletes, in particular Tiger Woods, as proof of this. I suspect that this is not true for women, as women can pretty much get access to casual sex at will. So, desirable woman attracts desirable man, desirable man is more likely to cheat because he has ass options. Desirable man attracts desirable woman, woman is less likely to cheat because she feels emotionally fulfilled.

This is something I wish the study had questioned. Were the women rated high in openness who were cheated on expecting strict monogamy (and what was the mean length of the relationships), or were they in some degree of an open relationship but their partners were still dishonest about outside relationships/sexual activity? I think that could make a big difference in the risk factors if we knew what the woman rated high in openness defined as cheating and their expectations on monogamy.

I don’t know what the questions were. Without having access to everything, all of these methodological discussions are bound to be fraught with speculation.

I agree with your second paragraph, and didn’t mean that there shouldn’t be any gender differences if there’s something to explain. My assessment of your general argument simply makes me expect the data to be more symmetrical. You’re kind of taking the parental investment and sexual selection stuff out of the equation and shifting to a more purely cognitive analysis. I wouldn’t expect a large gender difference in cognitive analysis, whereas I would in actual mating behaviors. Since we do see a large gender difference in the data, your explanation doesn’t strike me as fitting the data.

I just spent entirely too much time looking for the actual question that was asked… and failed. However, what I did see on the MIDUS surveys seemed to imply that the word 'spouse' (actually, spouse/partner is what I saw used) refers to a single person, not a list of current and/or former partners. I'll admit I didn't find a question that involved cheating or infidelity, and I didn't see the actual question used for data collection on the Inductivist blog either. Do you know what the actual wording was? It could make all the difference…

That being said, I would think that you, of all people, would at least consider that different characteristics were important for mate selection (and retention in the face of infidelity) for men and women. Considering all that we know (or kind of know, as the case may be) about human evolution relating to evo-psyche topics, it seems entirely reasonable to me that each gender type would have personality types more (or less) willing to abide cheating (or are more approachable for their spouse to admit infidelity). I am reminded of a paper that looked at imagined infidelity in couples and then the resultant emotions of insecurity and indignancy, which were different by gender. As in all things, the difference in potential parental investment between genders surely could skew the differences between men and women in this situation.

The monogamy-religiosity connection does benefit certain types of individuals more than others. Because of those interests, it's certainly a factor, but I don't think it's a sufficient explanation on the larger scale of human religiosity. In essence, this line of argument becomes a political one. I think the psychological arguments for religion are ultimately stronger.

I'm not compelled to assume the methodology was as poor as you do. My main reason for this is the complete lack of symmetry in the data for men and women. Since you basically suggest the same explanation for men and women, I'd expect the data to somewhat reflect the similarity. Could gender differences lead to the same causal reason being manifest through different personality traits in men and women? I suppose, but it's not a very satisfying explanation, and even in that case, I wouldn't expect to see the statistically significant traits demonstrate such disparity.

I also don't think we can assume that the measured cheating occurred with the current partner or in relation to their current relationship status. It appears that the study simply measured personality traits, and looked for correlations in the individuals associated with those traits — irrespective of current relationship status.

It seems likely to me that a cheating male spouse might be more willing to admit infidelity to an 'Open' spouse, and that that spouse might be willing to stick with the person that cheated on them. Conversely, a cheating male spouse probably knows better than to admit infidelity to a conscientious spouse (or if they do admit it, does the couple dissolve and then not be eligible for this study. )

I think the information is interesting, but I think there are some factors that prevent it from being a simple 'If you are X characteristic, you are more likely to be cheated on (or not cheated on)' story.