Upending predictions, young voters made a strong showing at the polls. Did they go because "everybody's doing it," as they saw on Facebook?
You didn't know it at the time, but when you logged into Facebook on Election Day, you became a subject in a mass social experiment. You went about your day, clicked around Facebook, and you may have voted. Now your behavior is data that social scientists will scrutinize in the months ahead, asking one of the core questions of democracy: What makes people vote? If patterns from earlier research hold true, the experiment's designer James Fowler says that it is "absolutely plausible that Facebook drove a lot of the increase" in young-voter participation (thought to be up one percentage point from 2008 as a share of the electorate). It is, he continued, "even possible that Facebook is completely responsible."
Assuming you are over the age of 18 and were using a computer in the United States, you probably saw at the top of your Facebook page advising you that, surprise, it was Election Day. There was a link where you could find your polling place, a button that said either "I'm voting" or I'm a voter," and pictures of the faces of friends who had already declared they had voted, which also appeared in your News Feed. If you saw something like that, you were in good company: 94 percent of 18-and-older U.S. Facebook users got that treatment, assigned randomly, of course.* Though it's not yet known how many people that is, in a similar experiment performed in 2010, the number was *60 million*. Presumably it was even more on Tuesday, as Facebook has grown substantially in the past two years.