Facebook changed Newsfeed to show how friend’s posts affect your emotions

In the latest edition of ‘what Facebook did to my Newsfeed today’, we have the story of how researchers manipulated the posts seen by 689 003 users to judge how updates with positive and negative words altered their emotions.

The study, which was published in the journal Proceedings of the National Academy of Sciences, was interested in figuring out if a stream of positive (or negative) status updates in the Newsfeed could have a noticeable affect on the emotional state of others, even without the type of verbal cues or face-to-face interaction that usually play a role in transferring emotions. And, as anyone who has ever left Facebook feeling worse than when they logged in can attest, it does.

The researchers (including Facebook data scientist Adam Kramer) controlled the content in around 0.05% of Facebook users Newsfeeds for a week in early 2012, and found that “when positive expressions were reduced, people produced fewer positive posts and more negative posts; when negative expressions were reduced, the opposite pattern occurred”.

The fact that users were exposed to an unusual number of negative or positive posts without their knowledge has raised some concerns, but the researchers were technically within Facebook’s Terms of Service (that thing you have to agree to in order to join but nobody reads). The company’s data use policy says that users’ data may be used for “internal operations, including troubleshooting, data analysis, testing, research and service improvement”, and researchers took that agreement as a sign of informed consent for the research.

Do no harm

In response to concerns, Kramer posted a public status discussing the research and the motivations behind it. According to the Facebook employee:

We felt that it was important to investigate the common worry that seeing friends post positive content leads to people feeling negative or left out. At the same time, we were concerned that exposure to friends’ negativity might lead people to avoid visiting Facebook. We didn’t clearly state our motivations in the paper.

Kramer explained that the research involved de-prioritising a very small percentage of content in the Newsfeed, depending if their was an emotional word in the post. Even if a post was pushed down the Newsfeed and not seen on first load, it was still available on the friend’s timeline, and the team didn’t change any private messages. The exposure to more negative posts also didn’t have an extreme affect on users — in the next week, they published an average of one fewer emotional word per thousand words.

The difference was small, but significant enough to prove that exposure to your Facebook friend’s emotions can have an affect on your own. In fact, it showed that it’s not only negative emotions that are influential — seeing happy posts on Facebook can make you more positive too.

It’s a finding that can help Facebook in the future — if you know that certain posts make your users happier, then you’d want to show them more of those so they keep using your site. It’s also a reminder to users that Facebook’s Newsfeed is a complicated beast, which is regularly tweaked and put through experiments to test its effectiveness. In case you weren’t aware.