FRIDAY, Feb. 13 (HealthDay News) -- If you're unattached this Valentine's Day and you're hoping to change that, you should know about this latest scientific discovery: Apparently, it's easier to judge how interested a man is than it is to tell how romantically intrigued a woman might be.

Men who are attracted to women, it seems, are more obvious and straightforward about that fact than women are. In fact, women often may act or look interested when they're actually not.

That's the bottom line of a new study in which observers looked at speed dating videos and tried to decide which men were attracted to which women and which women were attracted to which men.

While men and women observers performed equally well, "everyone is better at predicting male intention than female intention," said study author Skyler Place, a doctoral student at Indiana University, Bloomington. In several cases, a woman looked like she was being flirtatious, but it turned out she wasn't interested.

For the study, 28 women and 26 men, all college-aged, watched video clips of couples conversing on "speed dates" -- an event in which singles meet a large number of potential dates and spend a few minutes talking to each one. At the end of the event, each participant notes to program organizers which ones are a "match" for him or her, and then gets a list of mutual matches.

In the study, "they watched 24 different dates, and 48 people," Place said. The speed daters were speaking in German, as the speed dating took place overseas. The observers were English-speaking Americans who did not know German. This way, Place noted, the observers had to rely more on body language and less on verbal cues.

The observers' abilities to predict the interest of any one speed dater varied a lot, he found -- from 90 percent accurate down to 10 percent.

In five of the videos, 80 percent of the observers thought the women were interested in the men they were talking to, but they weren't, as noted on their decisions to not pick that person as a potential "match."

"We don't know why they acted friendly when they were not interested," Place said. The study did have some limitations. The observers only saw one interaction of each speed dater; if they had seen then all, the observers may have gotten better at reading interest levels in each speed dater, he said.