With the uproar continuing over Facebook's manipulation of some users' News Feeds to conduct an experiment on emotions, there are several things users need to understand.
News reports recently surfaced that Facebook enabled researchers to surreptitiously control the posts, comments and photos that about 700,000 users were seeing as part of a psychological experiment.
Users, analysts and bloggers have been voicing their outrage over what many are calling emotional manipulation and a breach of users' trust.
From how the experiment was conducted to its legality, what Facebook had to say and what recourse users have, here are seven things users e need to know.
1. What happened?
The Proceedings of the National Academy of Sciences (PNAS) published a study conducted by researchers from Facebook, the University of California and Cornell University on whether people's emotions can be influenced without face-to-face contact.
The study was conducted during the week of Jan. 11 to Jan. 18, 2012. It affected 689,003 English-speaking Facebook users.
In the experiment, Facebook temporarily influenced the kind of posts and photos users could see in their News Feeds, making it possible for researchers to show either mostly positive comments, posts and photos or mostly negative ones in order to see if the nature of the content influenced users' emotions.
As a consequence, users were not shown a regular cross-section of their friends' posts, but instead were given a manipulated feed.
Facebook noted that users could have seen their friends' content if they had gone directly to those Facebook pages, but much of that content was cut or emphasized on the News Feeds, which is where most users get their social information.
2. What the experiment showed
The study found that users who saw more positive comments made more positive comments themselves, while users who saw more negative comments echoed those comments.
The research is focused on what scientists call an "emotional contagion," or the ability to influence people to show the same emotions without direct personal contact or even their awareness.
3. Does Facebook normally manipulate your News Feed?
Yes, but it's not normally done to either cheer you or depress you as part of a psychological study.
Facebook has been upfront in saying it uses an algorithm that determines which stories appear first in users' News Feeds.
The social network has said it uses the algorithm to spare users from "spammy" content, duplicates and like-baiting, a method to boost circulation by actively trying to get users to like, comment or share a post. Facebook has noted it's trying to provide the information users most want to see.
"Ideally, we want News Feed to show all the posts people want to see in the order they want to read them," the company wrote in a post. "This is no small technical feat: every time someone visits News Feed there are on average 1,500 potential stories from friends, people they follow and Pages for them to see, and most people don't have enough time to see them all."
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