Tinder's sociologist reveals one big mistake people make in their profile photos

When I joined OKCupid back in 2012, it occurred to me that I needed to give people a really good reason to click on my profile, something to differentiate me from every other wavy brown-haired 20-something on there looking for a boyfriend.

And so I used a photo of me holding a sparkly mask in front of my face.

I know. But at the time it seemed so clever: Don't you want to know who's under there?!

I'd nearly forgotten about this unfortunate decision until I spoke with Dr. Jess Carbino, Tinder's in-house sociologist, about some of the most common mistakes people make when crafting their Tinder profiles. Apparently, covering your face in your photo is a big one.

Carbino was talking specifically about Tinder, but the same logic likely applies to online dating in general.

She advises against wearing anything that covers your face - glasses, sunglasses, even a hat. That's because people use your facial features to make judgments about your personality traits, and therefore to determine if you'd be a worthy mate.

Psychologists call it "thin slicing." According to Carbino, we take "thin slices of information and in a very quick period of time make very accurate judgments about somebody."

Note that Carbino said accurate there.

One study found that we can tell how extroverted someone is from a single photo of their face; another found that people were able to judge how trustworthy someone was based only on a facial photo.

Carbino gave another example of how thin slicing works: We often assume that men with softer jawlines are kinder and more approachable than men with stronger jawlines. Other research suggests that's because men with stronger jawlines tend to have higher levels of testosterone, which is related to aggression.

Interestingly, Carbino said we often make these judgments unconsciously. Indeed, in those studies on perceiving aggression and extroversion, people saw the facial photos for less than one second.

Bottom line: Hiding your face doesn't just make you look sketchy. It also means you miss the chance to convey to other users that you're trustworthy and friendly (assuming you are), and to attract someone whose personality is well-suited to yours.

Making these kinds of judgments about others, Carbino said, "helps us categorize our life when we're walking down the street. We're trying to assess if somebody is like us, dangerous, what have you. In dating, it's: Is this person compatible with us?"