Allow me to respond to your questions sequentially.
1. In regard to lower numbers of men than women on campus:
There actually is some research validating that there are more women graduating from college, and holding graduate degrees, than men.
Here is a link to a govenment study, including the statistics on lower percentages of males than females aspiring to college.
http://nces.ed.gov/pubs2012/2012046.pdf
Here is a scholarly report from the National Bureau of Economic Research, from 2006, discussing this same issue.
http://www.nber.org/papers/w12139
My own views as to why this is are probably varied across several paradigms of thought. Economically, I believe women are driven more to take care of themselves and their children, and more women/mothers are single -- either through divorce or through postponing marriage -- than previous generations. Rather than viewing men as the providers, I believe today's women view themselves as their own providers. I know I personally would not wish to entrust my financial wellbeing and future blindly to someone else.
Sociologically, it might be that with the advent of more rights and more equality for women in the past 40 years or so that women are trying to take advantage of opportunities previous generations did not have.
Another thought, then, is that perhaps men are becoming somewhat demotivated since they no longer bear the entire financial burden of raising a family, as per the 1950's and 1960's. Men born in the 1970's and beyond seem to have no problem with women being the primary providers. Some of these men that I have encountered would have no problem with women being their sole provider.
2. how aggressive are men sexually? That is a generalization that is not quite fair to men across the board. Some men are very aggressive and presumptive, others are polite and courteous. I think the venue in which you find men can potentially drive how sexually aggressively they behave. For example, I have noticed that at fighting events, it is not uncommon for fights to break out amongst the spectators. There is evidence that watching fights, and scantily clad women, increases the testosterone of the viewer. Thus, perhaps men in that environment might behave more aggressively than they would in, say, a classroom.
Here is a Peer Reviewed article about testosterne changing through the vicarious experience of winning or losing at sporting events.
http://www.sciencedirect.com/science/article/pii/S0031938498001474
Ringer, I looked up the abstract about adult porn actresses, and while the abstract reports that "In terms of psychological characteristics, porn actresses had higher levels of self-esteem, positive feelings, social support, sexual satisfaction, and spirituality compared to the matched group," there are some influential factors missing here.
My area of expertise is in personality and motivation. Those who are in the performance industry show higher levels of narcissism when tested for Narcissistic Personality Disorder than do those of the general population. Dr. Drew Pinsky collected data on his celebrity subjects and wrote about this in his recent book. Narcissists automatically have high self esteem. They are not plagued with self-doubt or the need to question their decisions, and they are lacking in a normal empathetic response to others that is one of the hallmarks of NPD. I would need to see more of this study and what the aspects of the control group, but it looks to me as though assumptions were made about self-esteem without consideration of some other heavy variables -- such as personality.
Here is a scholarly article that notes that "High self-esteem does not prevent children from smoking, drinking, taking drugs, or engaging in early sex. If anything, high self-esteem fosters experimentation, which may increase early sexual activity or drinking, but in general effects of self-esteem are negligible."
http://psi.sagepub.com/content/4/1/1.short
Here is a non-scholarly article about actors and the ubiquitous NPD:
http://theinneractor.com/100/are-performers-raging-narcissists/