Hitting It Off, Thanks to Algorithms of Love

PASADENA, Calif. — The two students in Southern California had just been introduced during an experiment to test their “interpersonal chemistry.” The man, a graduate student, dutifully asked the undergraduate woman what her major was.
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Further Reading
"Helping Singles Enter Better Marriages Using Predictive Models of Marital Success." Steve Carter and Chadwick Snow. American Psychological Society meeting, May 2004 (PDF)
"Similarity, Convergence and Relationship Satisfaction in Dating and Married Couples." Gian C. Gonzaga, Belinda Campos, Thomas Bradbury. Journal of Personality and Social Psychology, July 2007. (PDF)
"Couple Similarity and Marital Satisfaction: Are Similar Spouses Happier? " Ruth Gaunt. Journal of Personality, October 2006.
"Why We Love: The Nature and Chemistry of Romantic Love." Helen Fisher. Henry Holt, 2004.
"Finding Your Perfect Match." Pepper Schwartz. Perigee, 2006.
"How Do I Love Thee?" Lori Gottlieb. Atlantic Monthly, March 2006.

“Spanish and sociology,” she said.

“Interesting,” he said. ‘‘I was a sociology major. What are you going to do with that?”

“You are just full of questions.”

“It’s true.”

“My passion has always been Spanish, the language, the culture. I love traveling and knowing new cultures and places.”

Bogart and Bacall it was not. But Gian Gonzaga, a social psychologist, could see possibilities for this couple as he watched their recorded chat on a television screen.

They were nodding and smiling in unison, and the woman stroked her hair and briefly licked her lips — positive signs of chemistry that would be duly recorded in this experiment at the new eHarmony Labs here. By comparing these results with the couple’s answers to hundreds of other questions, the researchers hoped to draw closer to a new and extremely lucrative grail — making the right match.

Once upon a time, finding a mate was considered too important to be entrusted to people under the influence of raging hormones. Their parents, sometimes assisted by astrologers and matchmakers, supervised courtship until customs changed in the West because of what was called the Romeo and Juliet revolution. Grown-ups, leave the kids alone.

But now some social scientists have rediscovered the appeal of adult supervision — provided the adults have doctorates and vast caches of psychometric data. Online matchmaking has become a boom industry as rival scientists test their algorithms for finding love.

The leading yenta is eHarmony, which pioneered the don’t-try-this-yourself approach eight years ago by refusing to let its online customers browse for their own dates. It requires them to answer a 258-question personality test and then picks potential partners. The company estimates, based on a national Harris survey it commissioned, that its matchmaking was responsible for about 2 percent of the marriages in America last year, nearly 120 weddings a day.

Another company, Perfectmatch.com, is using an algorithm designed by Pepper Schwartz, a sociologist at the University of Washington at Seattle. Match.com, which became the largest online dating service by letting people find their own partners, set up a new matchmaking service, Chemistry.com, using an algorithm created by Helen E. Fisher, an anthropologist at Rutgers who has studied the neural chemistry of people in love.

As the matchmakers compete for customers — and denigrate each other’s methodology — the battle has intrigued academic researchers who study the mating game. On the one hand, they are skeptical, because the algorithms and the results have not been published for peer review. But they also realize that these online companies give scientists a remarkable opportunity to gather enormous amounts of data and test their theories in the field. EHarmony says more than 19 million people have filled out its questionnaire.

Its algorithm was developed a decade ago by Galen Buckwalter, a psychologist who had previously been a research professor at the University of Southern California. Drawing on previous evidence that personality similarities predict happiness in a relationship, he administered hundreds of personality questions to 5,000 married couples and correlated the answers with the couples’ marital happiness, as measured by an existing instrument called the dyadic adjustment scale.