Is Facebook getting more and more evil?
Turns out the social network secretly used almost 700,000 of us as guinea pigs to see if they had the power to manipulate our emotions.
It spent one week in January of 2012 showing some people mostly negative posts from their friends and filtering out the good ones. They also showed some people mostly positive posts and filtered out the negative ones.
Then they monitored those people to see how it affected them. Did the people who mostly saw negative stuff become bummed out and post more negative stuff themselves? Did the people who saw positive stuff become happier?
Fortunately, they found they can't manipulate our emotions. There was no connection between the posts people saw and how their moods changed.
The study was technically legal. You give permission to Facebook to do stuff like this by being a member of their site.