"Online dating is a terrific addition for singles to meet. That said, there are two problems," report author Eli Finkel, an associate professor of psychology at Northwestern University, said in an interview.

First, poring over seemingly endless lists of profiles of people one does not know, as on Match.com, does not reveal much about them. Second, it "overloads people and they end up shutting down," Finkel said.

He compared it to shopping at "supermarkets of love" and said psychological research shows people presented with too many choices tend to make lazy and often poor decisions.

The study's authors also questioned the algorithms employed by sites such as eHarmony.com to match people based on their interests or personality - comparing it to having a real estate agent of love.

While the algorithm may reduce the number of potential partners from thousands to a few, they have never met and may be as incompatible as two people meeting at random, Finkel said, adding the odds are no better than finding a relationship by strolling into any bar.

"Eighty years of relationship science has reliably shown you can't predict whether a relationship succeeds based on information about people who are unaware of each other," he said.

The algorithms are proprietary and were not shared with the researchers. "The assumption is they work. We reviewed the literature and feel safe to conclude they do not," he said.

He dismissed the dating websites' own studies on their success as unscientific, and said there are as yet no objective, data-driven studies of online dating. The researchers reviewed the literature on online dating and compared it to previous research.

Finkel said he and four psychology professors from other schools were enlisted by the Association for Psychological Science to write about the online dating industry, and the report was being published in the organization's journal, Psychological Science in the Public Interest.

Perhaps solving what Finkel termed the "original sins" of online dating are mobile dating websites such as Badoo.com and Zoosk.com. The sites offer some information about other members but more importantly allow participants visiting a museum, say, to ask others logged on nearby to meet up.

"There's no better way to figure out whether you're compatible with somebody than talking to them over a cup of coffee or a pint of beer," Finkel said.

(Reporting By Andrew Stern; Editing by Eric Beech)

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