Once a student has sex, it becomes less of an issue in future relationships.

," but don't hold its too-cute title against it—looked at how and when high-school students choose mates and their preferences when searching for a partner.

A tamer version of that observation is borne out in the economists' work among high schoolers.

high school senior dating sophomore-6

In the Darwinian world of high-school dating, freshman girls and senior boys have the highest chances of successfully partnering up. And they have found that for the most part, they're accurate.

Now, however, social scientists have examined them exhaustively and empirically.

Where there are more girls, the male preference for sex tends to win out.

Of course, all this raises a question that has long bedeviled scores of Y. novelists, not to mention millions of teenagers: In high school, how exactly does one define a "relationship"?

Unsurprisingly, the majority of high school girls do not (though 50.1 percent of senior girls do).

Over the course of four years, the power shifts from the freshman girls who don't want to have sex to the senior boys who do. Though high-school girls don't really want to have sex, many more of them end up doing so in order to "match" with a high-school boy.

Relatively little such data exists for teenagers, who mostly work the old-fashioned meet-someone-in-homeroom way.

But in examining the Add Health data, he and his colleagues found one classic economic tenet driving the byzantine high-school dating market: Scarcity determines value.

—interested in sex, whereas girls, no matter how boy-crazy, tend to focus on relationships.

Young men frequently fib about their sexual experience, whereas young women tend to be more truthful.

Among freshman boys, what's rare, and therefore valuable, are freshman girls willing to have a relationship and, even better, willing to have sex.