If you want to get to know someone, you could invite him or her out for coffee... or you could just look at their profile picture.

A new study published from the University of Pennsylvania found that your personality can be analyzed from the type of social media profile picture you post.

Researchers analyzed more than 66,000 Twitter profile images and estimated people's personalities based on their tweets. They found that there were "significant differences in profile picture choice between personality traits, and that these can be harnessed to predict personality traits with robust accuracy."

Here are some of the findings:

1. Neurotic people usually don't include their faces in their photos.

Neurotic people have a tendency to omit faces from photos and stick to less vibrant colors, the researchers found. If a face is present, the neurotic person usually displays a lack of positive emotion. 

2. Conscientious people like to smile.

People whose personalities are associated with orderliness, planned behavior, and self-discipline display images with joyful expressions and prefer to post a picture of just themselves. 

According to the study's authors, "this does not align with what is generally known about conscientious people, but is explainable by taking in account that in a profile picture, a person is expected to smile and appear happy." In an emailed statement to ATTN: one of the study's authors, Leqi Liu, told ATTN: said that this was the most unexpected finding in their research.

3. Open-minded and intellectual people use high-quality photos.

Such people display photos with increased contrast, better saturation, and less blur, researchers found. But they may not post images that feature themselves. 

4. People who get along with others show a variety of positive emotions.

Like conscientious people, agreeable people favor colorful images and those in which they smile. But agreeable people tend to post profile pictures that are not the most aesthetically pleasing, researchers said.

5. Outgoing people really like colorful images and prefer to have other people in them.