How shocking: Facebook had the temerity to conduct an experiment on its users without telling them and now the results have been published in the Proceedings of the U.S. National Academy of Sciences. Actually, no one should be surprised.
For a week in 2012, the social network’s staff scientist Adam Kramer and two collaborators used algorithms to doctor the news feeds of 689,003 English-speaking Facebook users. They reduced the number of posts containing “positive” and “negative” words, tracked their lab rat users’ own posts, and found that their mood was influenced by that of the news feed. The term, well-known to psychologists studying real-world communications, is “emotional contagion.”