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What’s the One Best question to predict casual sex?

The science of sex, beer, and enduring love.

One of the secret appeals of studying psychology is the possibility that it will turn you into a sort of Sherlock Holmes: Able to use extremely subtle cues to make inferences about other people’s personalities and behavioral inclinations. “Mr. Jenkins is obviously something of a lothario, Watson. I was initially suspicious at his choice of a mauve cravat, but my suspicions were confirmed by the pattern of wear on his walking stick.”

Clinical psychologists hope to learn subtle predictors of whether a person will become depressed, organizational psychologists hope to find quick indicators of whether a job applicant will do well on the job, and consumer psychologists hope to discover hidden signals of whether a person will buy a particular product or not.

One of the behavioral inclinations that an average male psychology major often hopes to predict is whether a woman will sleep with him on the first date (for female psychology majors, this is usually a non-problem, akin to predicting whether a rat deprived of food for 48 hours will press a bar for a food pellet. For more on this basic sex difference, see my earlier post: The 7 worst things about being a male).

Christian Rudder is a young entrepreneur with a Harvard degree in mathematics, cofounder of a free dating website called OKCupid. The site has been tremendously successful, and has, according to Rudder, produced data on “hundreds of millions” of user interactions, as well as the various dating preferences and social attitudes of those users. Rudder has applied his mathematics training to analyzing these data, and he writes about them in amusing and informative ways. In "ten charts about sex" he demonstrated an ability to graphically depict complex data in lovely and simple ways. There’s a colorful dynamic graph depicting the relationship between a woman’s self-professed body weight (skinny, full-figured, obese, etc.), self-confidence, age, and sex-drive. Although it sounds complex, the graph nicely demonstrates that a woman’s sex drive rises dramatically until her late 30s, then drops just as dramatically, whereas her self-confidence steadily rises with age. Women who self-describe as “curvy” are decidedly more interested in sex, and more self-confident, compared to women who say they are “skinny,” a trend that holds throughout the lifespan.

For those who might be interested in relationships after the first date, Rudder also delved into the data set to find the three questions that best predicted whether couples actually hit it off with one another, and went on to become involved in a long-term relationship. He also checked to see what people thought were the best predictors. According to popular opinion, the best questions to predict whether you’d hit it off were: 1) Is God important in your life?, 2) Is sex the most important part of a relationship?, 3) Does smoking disgust you? Indeed, the answers to those questions predicted relationship satisfaction significantly better than chance. But the data suggested that you could predict compatibility more than twice as well by asking the following three questions: 1) Wouldn’t it be fun to chuck it all and go live on a sailboat? 2) Do you like horror movies? And 3) Have you ever traveled around another country alone? Those of you who have studied personality psychology will recognize those questions as linked to a personality trait called “sensation-seeking.” Rudder's data suggest the startling possibility that incompatibility on sensation-seeking may be even more important than incompatibility on religion, sex, and smoking. Although I’d be careful about jumping to so broad a conclusion without more data, it’s clear that questions about sensation-seeking are a good way to determine your future compatibility with a partner, regardless of whether you both share a taste for beer.

My thanks to Becca Neel (whose research I discussed in a recent blog title Men Steal Anger, Women Steal Happiness), who pointed me to this interesting data set.

Douglas Kenrick is author of Sex, Murder, and the Meaning of Life: A psychologist investigates how evolution, cognition, and complexity, are revolutionizing our view of human nature.

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Is opposition to pot-smoking really just fear of sex?

The 7 worst things about being a male.

The 7 BEST things about being a male. In responses to complaints about my whining in the above.

The cost of a woman vs. the cost of a man.

Ten charts about sex” Christian Rudder

the best questions for a first date” Christian Ruder