It turns out, resting bitchy face does have a scientific explanation to it. So before you start getting all riled up because of how someone looks, know that everything can be explained and that you should probably not judge them too much.

Two behavioral researchers from Noldus Information Technology, Jason Rogers and Abbe Macbeth, decided to do a little research on the topic.

They used Noldus’s FaceReader, mapping more than 500 points on the human face, to identify what features cause RBF. There are 8 basic emotions: happiness, sadness, anger, fear, surprise, disgust, contempt, and neutral.

Before starting, they had to establish a baseline with a group of expressionless faces which registered 97% in neutrality. The remaining 3% contained “little blips of emotion” but nothing significant.

Then they used faces of well known people with RBF such as Kristen Stewart, Kanye West, and Queen Elizabeth. The neutrality dropped to 94%. “The big change in percentage came from ‘contempt,’” Macbeth said. It was caused by having one side of the lip pulled back slightly. Or squinting the eyes.

“Something in the neutral expression of the face is relaying contempt, both to the software and to us,” said Macbeth. They also found that RBF is generally associated with women, Kanye West being one of the few male exceptions.

Read their entire study here.