Unscientific Assumption

I've read in more than one place that women, overall, are more attractive than men. And that just seems like a pretty ridiculous claim to me. I, for one, find men much more attractive.

The thing is, at least one of these claims was made in a book explaining some evolutionary biology ideas to the general public. As in, they were trying to explain why women are more attractive than men. In that context, I would want the basic claims made - the things that they are trying to explain - to be supported by solid scientific data. But how would you measure that? Most men find women more attractive. Most women find men more attractive. What did they do, see whether people primarily attracted to men are more likely to find women attractive as well than people primarily attracted to women are to also find men attractive? If so, they really ought to mention that research in the book. And I know they didn't because I would have remembered that sort of study.