In January 2012, for one week, Facebook deliberately manipulated the News Feeds of nearly 700,000 of its users as part of an experiment. News Feed is a constantly updating list of stories from people and pages that you follow on Facebook, and includes status updates, photos, videos, links as well as app activity.
Facebook wanted to know if users were affected in any way by what they saw. The company did not seek explicit consent beforehand, but claims its terms of service contract with users permits blanket "research".
In those few days, some users saw positive stories such as kitten videos, brownie recipes and happy emoticons, while others were force-fed depressing stories such as ill-health Fand breakups.
The researchers then concluded that there is something called an 'emotional contagion' or the Facebook term for what we call empathy.
It was found that users exposed to negative feeds posted more negative status posts while those exposed to positive feeds posted more positive posts.
Meanwhile, Facebook's Chief Operating Officer Sheryl Sandberg today admitted that the social networking giant had communicated poorly on a controversial psychological experiment, but denied any attempt to control the emotions of users.
In an exclusive interview to NDTV, Ms Sandberg, who is visiting India, emphasised that Facebook takes the privacy of users very seriously. "We communicated very badly on the emotions study... We hope users understand that we care about their privacy...We want to be transparent and give users control," she said.
News of the psychological experiment has caused anger among Facebook's more than one billion active users, with some calling it "super disturbing", "creepy" and "evil".
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