Men and Women Can't Be "Just Friends" (2012)
scientificamerican.com
scientificamerican.com
That said, I find it odd that the study found guys overestimated the woman's interest. That seems like wishful thinking. I always found it pretty clear whether or not the potential interest was returned. If it wasn't, it wasn't, and there's no sense messing up a nice friendship.
Taking a few steps back, to look at the big picture: It is pretty well established that - given the opportunity - men tend to be more promiscuous than women. Turned around: women tend to be more selective than men, and if they are not, it can lead to (or is tied to existing) mental health problems. For example, one NIH study shows "a strong association between number of sex partners and later substance disorder, especially for women".
I think it is more of an ego thing.
In fact, if the study was conducted among 50-year-olds in the United States, the results would most likely be significantly different.
IMX being just friends was very easy when both parties fell into each other's "never will" set.
Take the results with twelve grains of salt.