I last left you on the edge of your seat about what I’d write next about the study on extradyadic sex I introduced you to in my last post. If you have not already read the prior post, please do so as this one builds on it. That post was all about findings in a study from our lab at the University of Denver (Shaw, Rhoades, Allen, Stanley, & Markman, 2013).
Here’s a very brief recap: Shaw et al. examined predictors of having sex outside of one’s serious, unmarried, romantic relationship over a 20 month period of time. As you can read in the prior post, many variables were associated with new occurrences of infidelity in these relationships and many other variables were not associated with infidelity. For example, those who were happier and more committed and who had less negativity with their partners were less likely to report having had sex with someone else. Not shocking but good to know. In contrast, those who had a greater number of prior sexual partners or who reported more use of alcohol were more likely to report having had sex with someone else. And so forth and so on.
Did any of the findings seem surprising to you? The finding that I think many people would consider surprising is that living together was not significantly associated with whether or not a person reported having had sex with someone other than their partner. That is, living together was not associated with greater odds of cheating nor was it associated with lower odds of cheating. Living together just didn’t provide information about sexual exclusivity.
I believe that many people believe that cohabitation = commitment or that it means there has been a step-up in commitment. Closely related, I believe that many people believe the fact that two people live together means that the two partners are “off the market,” so to speak. There actually is no evidence that I know of for believing this.
From all of the studies I know, I have not seen convincing evidence that living together sends any clear signal about commitment between two people. That’s a problem for some people because they believe that it does. In contrast, other variables studied by Shaw et al. were associated with greater odds of exclusivity, for example commitment to one’s partner or engagement to marry.
As I’ve said before, if couple tells me they are living together, and this is all I know, I don’t know much about commitment. In contrast, if a couple tells me they are married, engaged, have mutual plans for marriage, or have a made a really strong, mutual commitment to a future together, I know a lot about their level of commitment. Those things are all strong and clear signals of commitment. And that’s really my point here. While I am reporting findings about sex and living together, the key underlying issue is about clear and unclear signals about commitment.
There is some practical advice in this. If you want to know if your partner is really committed to you, look for something that reflects actual commitment. Don’t rely on an unreliable signal—living together. Living together does not signal commitment. Commitment signals commitment.
As an aside, I’ve noted in other posts that I believe there are some places and conditions where living together does signal a higher level of commitment compared to not living together. But I want to point out that there is just not much evidence for this being true for most people in most communities.
The practical point is something like this: If you are trying to figure out if a relationship is exclusive and has a future, the starting point isn’t going to moving in together—nor would it be the willingness of someone to have sex with you. Moving in together does not mean much about commitment. It’s much more informative to talk openly (when it is the right time to start doing so) and see if there really is a mutual commitment and a similar understanding about relationship. Too many people find out the hard way that moving in together didn’t mean what they thought or hoped it meant.
[Technical note for those so inclined: Our sample is relatively large for the level of measurement that we have on these relationships over time. That means the lack of a significant association between living together and infidelity is not likely a result of having too little statistical power. Also, the analyses reported in Shaw et al. are not what you often see in sociological studies where many variables are controlled for while looking at the impact of one or two key predictors of something interesting. We’re psychologists, and I must confess we sometimes think sociologists over do their controls. The analyses in Shaw et al. are intentionally showing which variables among a substantial list are associated with new instances of infidelity, not what is associated with infidelity when many other variables are controlled for at the same time. I have, however, also looked at some related analyses with and without controlling for some other variables such as how long the person had already been in the present relationships. Same general finding: living together is not reliably associated with more or less odds of infidelity. There may be a more complicated or otherwise interesting story to tell in the future when we get to other analyses. We’ll see. The present finding is consistent and it fits other findings that shed light on what does and does not signal higher levels of commitment.]