Looking for love? Formula isn't online, report says If you're bemoaning the lack of a Valentine, chances are you've turned to what seem like a gazillion dating websites for help. Buyer beware, though, caution a team of psychologists who've just published a lengthy report about online dating, now a billion-dollar industry. "There are sites that will tell you, "based on decades of scientific research and basic math, we can find your compatible mate for you,"" says lead author Eli Finkel, an associate professor of social psychology at Northwestern University. That's a pretty tantalizing offer. The problem, Finkel says, is that these websites have no scientific evidence to back up their claims that they can find your soulmate. Well of course they don't. Science and romance go together like Demi and Ashton, right? Actually, Finkel says, scientists have been studying relationships for 80 years or so. And one thing is clear: It's impossible to determine that two people have what it takes to maintain a long-term relationship before they've even met. Research has shown that three types of information are needed to predict whether a couple will fall in love and stay in love, Finkel says. One is demographics. It helps if a potential mate is age- and geographically appropriate. A second, says Finkel: "What are the actual dynamics between two people who have met?" And last, "What are the life circumstances that affect the couple?" Finkel says. There's no way they could possibly know that a hurricane or a cancer diagnosis or a sexy coworker is around the corner. Probably the best-known matchmaking website is eHarmony.com, which charges $59.95 for a month's subscription. eHarmony asks clients approximately 250 questions about 29 "dimensions of compatibility," ranging from conflict resolution to kindness to ambition. eHarmony's "matching algorithm" is proprietary, so the company did not share it with Finkel and his coauthors. In a statement, spokeswoman Becky Teraoka said the proof of eHarmony's success is in the numbers. On average, she said, 542 people marry in the U.S. each day as a result of being matched on eHarmony, according to a 2009 study conducted for the website by Harris Interactive. "eHarmony's matching system is based on years of empirical and clinical research on married couples," Teraoka said. As part of this work, we have studied what aspects of personality, values and interest, and how pairs match on them, are most predictive of relationship satisfaction. Finkel isn't convinced. Speed-dating, which he's also studied, can tell prospective mates more about each other than profiles from a website, he says. The human mind was built to size people up pretty quickly. The human mind was not built to browse a profile and figure out whether somebody is compatible. If you're looking for love online, Finkel says, your best bet is to save your money and stick with the less-expensive websites in which you browse profiles, as opposed to those that try to make matches for you. But, warns Finkel, who met his wife the old-fashioned way through a fix-up arranged by their grandmothers, "get offline fairly quickly, because you're never going to be able to figure out from a profile and some emails whether you're compatible with somebody." How did you meet your partner? More from Today Health