If you have ever chosen a profile picture for an online dating site, you have probably tried to pick a shot that gets across some of your key traits—energetic, friendly, silly, warm. Yet recent research suggests that the people who see your photograph are probably not accurately gauging your personality. A new study finds that a short video can leave a much more accurate first impression.

Researchers at the University of Texas at Austin put together a speed-dating pool of about 200 men and women. They also took photos of the participants, mimicking those found on online dating sites, and recorded short videos of the same individuals to see what kinds of first impressions people would form in each context. For each scenario, participants rated those they “met” on traits such as attractiveness, humor, intelligence and other qualities that we usually judge within seconds. The researchers presented their findings in January at the Society for Personality and Social Psychology meeting in San Diego.

Ratings from the three groups showed that individuals were more likely to agree on what another person was like if they met face-to-face or saw a video of that person. But when they had only a picture to go by, the raters used more of their own beliefs and schemas to make judgments. When someone describes a static image, “it tells me more about the viewer than it tells me about the person in the photograph,” says senior researcher Paul Eastwick, an associate professor of psychology at U.T. Austin.

The reason we misjudge photos, the researchers say, is that the limited information contained in a photo puts us in an abstract mindset. We then draw on our past experience and expectations to fill in the blanks. A video, on the other hand, contains dynamic details that capture our attention and quickly reveal volumes about a person's personality—even if the clip is just a few seconds long. Someone's smile, voice and gestures, for example, provide instant clues about his or her agreeableness, trustworthiness and self-confidence.

Live impressions, of course, are the most powerful. So when you start warming up to a potential date online, Eastwick says, it is important to get to that meet-up at a coffee shop or bar so you can get a more authentic sense of the person. Meanwhile wily entrepreneurs are already creating dating apps based on videos, not photos.

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