Mar 16·edited Mar 16

Two major confounding factors jump to mind here:

The first is that questions of how and how often people are caught cheating, or disclose their cheating, and how those conversations play out is a really big deal.

Consider this, if every case of cheating was immediately discovered, and every case resulted in the immediate dissolution of the relationship. The cheating rate for ongoing relationships in a survey like this would be zero. So, in that sense, what you are actually measuring is not only cheating, but also the successful hiding of cheating, and the successful working through and past of discovered cheating. So when you see a spike in cheating in 20+ year relationships, one theory is that people are cheating more. But an equally valid theory is that people are becoming more likely to continue in a relationship where cheating has occurred.

(EDIT: This is literally survivorship bias. Asking people currently in relationships whether they have cheated and then drawing conclusions about how often cheating occurs in relationships is roughly analogous to asking pilots returning from bombing runs if they took a direct hit to the engine and then concluding that anti-aircraft guns pretty much never hit engines.)

The other confounding factor has to do with societal shift and technology. The accessibility and risk of cheating has changed dramatically in the age of tinder/grindr/etc. And this accessibility has disproportionately skewed younger. I think this becomes especially relevant when comparing against older data.

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Some evolutionary scientists, like David Buss, endorse the Mate-switching-hypothesis of cheating, which states that women cheat to find a new partner to replace their current partner. If this is true, it would open up an interesting question: Do women cheat less or is their cheating just more likely to end the relationship (which would mean it doesn't show up in as many statistics)?

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I would expect the sample to be biased towards "hornier than average." Sex drive generally drops with age, and most of your observed difference is in older population. If you are surveying folks that are hornier than average, and they are in population groups that are *less* horny than average, then they may have an even larger horniness gap than when they were younger. There may also be a threshold effect, where in younger cohorts, the sex isn't ideal, but is suficient to stave off cheating (say 2-4 times per month). If age causes sex to drop off to less than once per month, then this may be what motivates a partner to cheat.

Some interesting quetions to ask would be "How infrequent would sex need to be for you to consider cheating?" and, as a proxy to 'horniness', "How often would you ideally have sex?"

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Measuring actual cheating rate is interesting but what I would really like to know is how many men who had occasion to cheat did it or restrained themselves. I bet that in a world with cheating as avaiable as porn rate of cheating would be similar to porn usage - like above 90% or so. :P

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An obvious, enormous, elephant-sized issue is that here, by necessity, we keep treating self-disclosed admissions of cheating on surveys as a proxy for real cheating. Given that people will obviously lie about cheating, perhaps more than about anything else in the world of surveys, that's a huge deal.

In particular, what sort of factors will make someone hide their cheating on a survey, or tell the truth about cheating in a survey? Maybe age makes you more or less likely to disclose on surveys, for instance? Whichever factors affect that might very well dwarf any underlying effects on real cheating, leading us astray.

It's a hard problem to tackle and I don't see any great solutions to that.

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Your questions are unscientific and poorly specified (didn't, for example, test interpretation of language}; there's little reason to credit what people say in surveys in this area; there's sampling bias—one could go on and on. You have money, if you're interested in the topic why not pay to get good data? Then you can make a start at theorizing.

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On the Wikipedia graph: That one is from 1991, so before Viagra. So the decline above 50 is probably due to the fact that many older men simply couldn't cheat because they couldn't reliably get an erection. This changed.

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Mar 21·edited Mar 21

I took it and said yes to cheating, by which I meant kissing (not sex). So I believe a large share in the discrepancy could have to do with the fact that “cheating” doesn’t just include sex. I’m F.

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An additional study on the topic.

The danish sexus https://files.projektsexus.dk/2019-10-26_SEXUS-rapport_2017-2018.pdf (sorry that it is only available in danish) the relevant section is pages 407-409.

sample of 47379 after restricting to people in relationships. 23.1% of men and 13.8% of women had been unfaithful to their current partner

Looking at the crosstabs for statistically significant effects (at the 5% significance level)

The capital region is more unfaithful with the rest of the country broadly similar (after adjusting for age and gender)

Gay and bi men are more unfaithful than straight men (after adjusting for age), bi men are higher than gay men.

Bi women are more unfaithful than straight and gay women (who are not significantly different)

It isnt statistically significant that unmarried people are more faithful (after adjusting for age and gender) than married people, although the data leans that way (95% confidence [0.85, 1,00] on the ratio of cheating compared to married people)

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