I wish I had a source to back this up, but from what I read in college from my Sociology classes... statistically speaking men tend to marry (or are attracted to) women who are below their socioeconomic status.
Another way to say that is that women tend to marry (or are attracted to) men who are above their socioeconomic status.
Since I expect that most people – men and women – would rather move up than down, what would that imply about the relative weight of preference?