Although mathematicians and psychologists do not often agree, they offer the same advice when it comes to sex: don’t give it up on the first date. According to a numerical model they developed, the good guys were willing to date for a longer time before having sex, while the rotten apples were reluctant to stick around.

The model is based on the idea that a woman will get a positive payoff from mating only if the man is a ‘‘good’’ male, with respect to his genetic quality, or ability orintention to provide paternal care. If she decides to sleep with a ‘‘bad’’ male, she will get a negative payoff from mating with him. In addition, a ‘‘good’’ male is willing to court for longer than a ‘‘bad’’ male; in this way the dura-tion of a male’s courtship signals his type, and acts as a costly handicap.

Die a virgin“Long courtship is a price paid for increasing the chance that mating, if it occurs, will be a harmonious match which benefits both sexes,” says professor Robert Sey-mour, leading author of the study. His colleague, Dr Peter Sozou, explains: “The strategic problem a female faces is how to screen out bad males, and this is where long court-ship comes into play. A male is assumed to always want to mate with a female, but a good male is more willing to pay the cost of a long courtship to claim the prize of mat-ing. So the female’s strategy is a compromise, a trade-off.” What the equations do not reveal is how long men should be kept waiting, in light of the fact that not even good guys will necessarily wait forever. Deciding on the length of courtship is thus a matter of judgement - which isn’t much help for women of a certain age. Also, a woman cannot eliminate the risk completely unless she decides

Mathematicsnever to mate. Apparently, there’s only one way to avoid the chances of picking a dud guy altogether: die a virgin. So, back to your perfect first date. He or she is still waiting for your answer. “Are you com-ing with?” In the end, it all depends on what you’re looking for. If you just want to have

some fun, don’t hesitate, go. If you’re aim-ing for a long-term thing, however, kindly de-cline and go home. Alone. You’ll thank your-self later.