In terms of recent news that generated outrage, few stories in the past month can compete with the Facebook “Mood Manipulation” Experiment. If the story escaped your notice, here’s the basics: A study conducted by Facebook’s data team filtered 689,003 users’ News Feeds for positive or negative keywords. The test was to see what impact this had on the users’ subsequent posts. Needless to say, users with only positive Feeds were more likely to say something positive. Negative Feeds led to more negative posts.