4. What has Facebook said about the experiment?
Adam Kramer, a data scientist at Facebook who was involved in the study, apologized for upsetting users in a post on his Facebook page.
"Having written and designed this experiment myself, I can tell you that our goal was never to upset anyone," Kramer wrote. "I can understand why some people have concerns about it, and my coauthors and I are very sorry for the way the paper described the research and any anxiety it caused. In hindsight, the research benefits of the paper may not have justified all of this anxiety."
He pointed out that the research affected only about 0.04% of Facebook's users, or 1 in 2,500. The social network today has more than 1 billion users.
5. Is this legal?
The short answer is yes.
The study's authors noted in their research paper that users accept Facebook's right to manipulate their News Feeds when they click on the site's terms and conditions of use.
Patrick Moorhead, an analyst with Moor Insights & Strategy, noted that Facebook's user agreement states clearly that the company can do research on people who agree to the site's terms.
"Legally, even if people never read the terms, they are still bound to them," Moorhead added. "There are exceptions in the U.S. on things like bank loans and insurance documents, but this is not one of them."
6. Is it ethical or fair?
That, say industry analysts, is another matter all together.
"The biggest complaint is Facebook's mind frame -- their lack of care about customers and protecting their privacy," Kagan said. "It's about the sneaky approach that Facebook continually seems to take and not caring about the concerns of the users."
Rob Enderle, an analyst with the Enderle Goup, said the drawback to free sites and services is that users may lose control over their privacy.
"A big part of the cost of 'free' is that companies often don't value customers who don't pay them for their services," Enderle said. "There is a growing elitism in the technology market likely connected to the massive power and wealth imbalance between the people who control social media properties and those that invest in and use them."
7. What options do users have?
While analysts say they'd be surprised if there wasn't a class-action lawsuit filed over this move, they also note there's a very easy step that users can take.
Quit. Just stop using Facebook. The issue is that Facebook has had privacy issues and angry users in the past and there has never been a mass exodus.
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