If you think women generally have a higher sense of self-worth than men, you should really take a look at the prevalence of anorexia, bulimia and depression in women vs men.
I think it's more general than that: everyone has higher perceived self worth than they actually have. And so the response rate sucks in general, since everyone's going after folks outside their league and never settling for what's actually reasonable for both parties.
Some truth to that, but in general women are more selective than men. Men have a much higher range in terms of IQ, attractiveness, personality, etc... than do women who tend to fall toward a median.
