The next time you log onto a dating site, you might want to add “mysterious” to your list of desired traits, because the less you know about a potential mate the better.

A new study of romantic relationships finds that as online daters got to know another person over time, their initially sweet notions turned sour. The researchers suggest that inflated expectations can lead to major disappointments when daters meet in person. Once a flaw is spotted, the whole date is tainted.

Fantasies vanishing with knowledge is a process that hits women harder than men, said Michael Norton of Harvard Business School and one of the study's authors.

“On online dates, women are much, much more disappointed than men," Norton said. Women put more stock in the virtual dating world because they seek a soul mate, he said, whereas men are typically after a more casual relationship.

It's not that familiarity always breeds contempt, the researchers say. But on average, as you learn more about any lover, the less likely it is that you will click and get along with them, Norton explained.

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Norton and his colleagues, including Dan Ariely of MIT and Jeana Frost of Boston University, initiated the study with the help of online dating services like eHarmony and Match.com, though he refused to say which specific ones. “We were working with a couple of online dating companies who were finding that their users got very unhappy very quickly with online dating. And the question was why,” Norton said.

To find out, they showed each of 304 online daters, average age 34, a grab-bag of anywhere from one to 10 traits randomly culled from more than 200 characteristics gathered from real online daters. Each online participant rated how much they liked their potential date, as well as which traits they would also use to describe themselves.

Participants gave much lower ratings to potential dates and also perceived less similarity with them when they were shown greater, rather than fewer, numbers of traits.

The results are detailed in the January issue of the Journal of Personality and Social Psychology.

More evidence

Two additional experiments backed up this finding. In one, scientists asked each of 190 students to complete a Web-based survey in which they were shown 10 traits, one at a time. After seeing each trait, subjects would indicate whether that trait also described them.

The first trait had a negative amplifying effect, the scientists found. If subjects said the first trait failed to describe them, they were more likely to say the same of subsequent traits presented to them. The opposite was found if the first trait got a positive score.

“Inevitably, I’m going to find something we don’t agree on. And as soon as I find that one thing, then things start to cascade so everything else I learn about you suddenly now feels like more evidence that we are dissimilar and we don’t get along,” Norton said.

“Once you start this process of saying, ‘Ah, it’s not going well,’ it’s like an avalanche basically,” Norton said.

In the second reinforcing experiment, scientists surveyed two groups of online daters. Subjects in one group answered questions about an upcoming date. The other subjects answered questions about a past date.

These results also showed that getting to know a person is a real downer for romance. The scores given to pre-dates were much higher than those for post-dates. And the perceived degree of similarity between participants and dates also took a dive after face-to-face encounters.

Fantasy date?

Online profiles inherently provide limited pictures of people, a level of vagueness that is fuel, Norton said, for love-seeking imaginations.

“Because people so much want to find somebody, we find that they read into the profile. They kind of see that person as a good match for them, and that they have a lot in common,” Norton told LiveScience.

“And when they finally meet in person, they find out it’s just a regular person like everybody else. They end up being disappointed again.”

Little white lies add to the inflated expectations. “One of the reasons people are so optimistic when they read these things is because everybody kind of shades their profile a little bit more positive then maybe it should be,” Norton said.

A separate recent study of four dating sites—Match.com, Yahoo Personals, American Singles and Webdate—revealed common fibs in the name of love. Profiles were corroborated with real-life measurements of a sample of users. About half of the men lied about their height, adding at least a half inch to their stature, while more than 60 percent of all participants skewed their weight by five pounds or more.

Match tips

Norton and his colleagues are developing ways for online daters to stay grounded in reality as they navigate the virtual world of romance.

In one study, Frost, the MIT researcher, designed an online interface in which people meet for “virtual dates.” For instance, you and a prospective date would each play an avatar and wander through an art gallery together. Though it’s nowhere near an in-person encounter, Norton said you can get a feel for whether the person is funny or a good listener.

“People also will use their avatars to flirt so you can go a little closer or a little farther away,” Norton said.

The main message from the group’s study, Norton said, is that people should realize that the rules for online dating and real-world dating are the same. In the real world, “You’re accustomed to it being difficult to find people; you’re accustomed to meeting people and not really clicking,” Norton said. “Don’t assume that because you log onto a Web site and there are all these options that it’s going to be any easier.”

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