NEW ORLEANS — The phrase “opposites attract” has a romantic ring to it.

It has a touch of science — isn’t that how electricity works? — mixed with the lure of the unknown.

But researchers at the online dating site eHarmony say that people who are more alike than different have a better chance at being a happy couple.

“Can relationship science tell us which couples end up happy?” asked Gian Gonzaga, senior director of research and development at eHarmony.

Yes, he said, it can.

The issue is of interest.

Online Dating Magazine, in January 2011, reported that there are “more than 280,000 marriages a year as a direct result of people meeting on an online dating service.”

The top two giants in the online dating industry, it reports, are and

Gonzaga, who holds a doctorate in personality-social psychology from the University of California, Berkley, spoke at an international conference of psychologists in New Orleans. The 14th annual meeting of the Society for Personality and Social Psychology brought more than 3,600 scientists to the Crescent City on Jan. 17-19.

The society, according to its website at, is the largest organization of social and personal psychologists in the world.

Its 2013 conference at the Ernest N. Morial Convention Center officially kicked off on the evening of Jan. 17, with 89 presentations made through the weekend, on a wide range of topics.

Prior to that, however, preconference seminars were also offered on topics of interest to society members.

And among the seminars was the one on online dating, part of a slate of preconference topics under the heading of “Close Relationships.”

“One of the things that (has been) written is that relationship research hasn’t done such a good job in predicting the future of relationships,” Gonzaga said.

“I disagree,” he said.

eHarmony, established in 2000, uses a patented “compatibility matching system,” according to its website,

Gonzaga described to the audience how eHarmony researched and developed one of the algorithms it uses to predict a couple’s chances of their relationship growing and staying strong over its lifetime.

To develop the algorithm, the company undertook several studies with different, independent samples of married couples, recruited via online panels.

In the studies, both spouses were provided an online link with extensive questionnaires on such items as personality descriptors, emotional tendencies descriptors, interests, partner preferences, personality statements and measures of relationship satisfaction, Gonzaga said

To validate the study models, “We went with longitudinal studies” each conducted over several years “that allowed us to predict change over time and see if compatibility measured before partners ever met predicted relationship satisfaction years later,” he said.

The findings showed that “compatibility ... predicted relationship satisfaction, up to four years later,” he said.

In a commentary following Gonzaga’s presentation, Harry Reis, professor of psychology arts, sciences and engineering at the University of Rochester in Rochester, N.Y., urged Gonzaga to submit eHarmony’s research to peer review.

Gonzaga had mentioned the subject earlier but said that industry competition made such a move to be unlikely on the part of eHarmony.

Reis also suggested that eHarmony devise a way to conduct a randomized control study on the subject of couples’ chances for happiness.

In such a study, participants are randomly assigned into an experimental group or a control group.

Gonzaga had earlier said that such a study would be “prohibitively impractical and expensive and potentially unethical.”

Reis said that tools used to predict a couple’s potential for happiness should go through as rigorous a process as that for medical devices and pharmaceuticals.

“I’m going to suggest to you that relationships are as important to people’s health and happiness as any health condition you want to see,” Reis said.

The subject of online dating gets people’s attention, he said.

“If I say ‘online dating’ in a college class, the students actually put down their cellphones and listen,” Reis said.