12 September 2012—Back in the day, when your mother asked you whether you’d jump off a bridge if your friends did it, her aim was to demonstrate the perils of being a follower. But we’re all followers now, and peer pressure isn’t necessarily negative. That fact was made abundantly clear in an experiment conducted by researchers at the University of California, San Diego. In a report published this week in Nature, they show that the online influence of peers could get voters to the polls.
On the day of the 2010 national election, they used all adults in the United States who logged on to their Facebook accounts as guinea pigs. Of the 61 million voting-age Facebook users who went to the site that day, roughly 98 percent were shown a “social message” that appeared at the top of their news feeds. This message not only encouraged users to vote and provided information about how to find their local polling places, but it also displayed a clickable “I Voted” button. People randomly assigned to the social-message group were also shown a counter that kept track of the total number of Facebook users who had clicked their “I Voted” buttons, and as many as six randomly chosen profile pictures of their Facebook friends who had done so.
The remainder of the U.S. adults who accessed their Facebook pages that day were randomly split into two groups: One was an “informational message” group, which was given all of the aforementioned cues except for the profile pictures of Facebook friends who had clicked the “I Voted” button. The other was a control group whose members did not receive any voting-related messages at the top of their news feeds.
All told, 6.3 million people clicked the “I Voted” button that day. The UCSD researchers concluded that, based on comparisons with publicly accessible voting records, the experiment led roughly 340 000 people to vote who otherwise wouldn’t have. But the really important part came when the researchers looked at a breakdown of the additional voters. “For every one person we got to the polls directly [just because of the information provided in the message], we got four friends,” says James H. Fowler, a political science professor who is a member of the research team.
Fowler says that the group plans to study how this effect, known as “social contagion,” can also be used to promote better health behaviors, whether they be physical or mental. Researchers are aware that emotions spread more easily through weak ties (a neighbor or casual acquaintance) than behaviors do. “Strong ties,” such as family members and close friends, says Fowler, “got people to the polls; weak ties got them to hit the ‘I Voted’ button.”
Either way, social scientists now have proof that a message spread online can affect what people do in the real world. So if your mother had asked, “If several of your friends told you that they voted today, would you run right down and cast your ballot?” there’s a good chance the answer would have been yes.