Facebook Deliberately Experimented on Your Emotions, by Sam Biddle.

Imagine a company that records every detail of your biography, can recognize your face, tries to listen in on you through your phone, and stores countless messages between you and your friends. Now imagine this same company intentionally making you sad. It happened.

The findings of Facebook’s psychological experiment, which turned 689,003 users into test subjects without their consent, were recently published in the Proceedings of the National Academy of Sciences. The paper, a horror-show of anti-ethics, presents an online reality that’s ominous to the point of parody. …

In short, these almost 700,000 users were artificially (and arbitrarily) shown Facebook posts in an attempt to alter their mood enough to share similar happy or sad posts. … The experiment was a success: Facebook’s research concludes that it can indeed make you feel what Facebook wants you to feel, and to a certain extent post certain kinds of things.