As the Supreme Court took up the case of marriage equality last week, some 2.7 million people changed their Facebook profile picture to a white equal sign on a red background in solidarity. This is just one example of how social media mobilizes people around the world for a common cause.
In a recent study, researchers simulated how people could use social media (such as Facebook and Twitter) to find 10 weather balloons, hidden randomly throughout the continental United States, over the course of several hours. They demonstrated it was possible to find the balloons using social media alone, without any help from traditional mass media, like TV or radio broadcasts.
The findings show that highly connected people with broad geographic social networks are essential to the successful mobilization of society, the researchers say. The findings were detailed today (April 1) in the journal Proceedings of the National Academy of Sciences.
Social media strategy
Social media sites allow society to mobilize in response to challenges that require collaboration, such as natural disasters, search-and-rescue efforts and climate change, said study leader Iyad Rahwan, a computer scientist at Masdar Institute in Abu Dhabi. In the age of the Internet, cellphones and social media, "we are able to communicate instantly with large numbers of people, form ad hoc teams at a very large scale and exchange crucial information in a timely manner," Rahwan said.
"But despite all of this promise, our scientific understanding of the processes underlying social mobilization in the Internet age is still lacking," Rahwan told LiveScience.
Rahwan and his colleagues studied how social media could be used in the balloon-finding task, which was part of the 2009 DARPA Network Challenge. The team's simulations showed that using social media alone resulted in a 90 percent chance of finding all the balloons, but all the conditions had to be ideal — "the perfect storm," Rahwan said.
The researchers ran simulations of the balloon-finding task, using geographic and demographic information about the participants. They focused on the strategy of the winning team, which was from MIT.
Rallying thousands of people requires leaders who respond rapidly, have many connections and forward information much faster than the average person, the researchers found. In addition, passive participants, who don't recruit others but may help with the task if they were to come across a balloon, play an important role.
Being successful also relied on the "small world" phenomenon. In other words, random friendships that spanned big geographical distances were successful in mobilizing people because these long-range connections quickly spread the word about the balloon search, Rahwan said.
The "findability" of the balloons depended on both the population density of the people searching for them and how well the balloon was camouflaged, the researchers found. Objects may be easier to hide in densely populated areas, like Manhattan, than in areas with medium-density populations, because they can blend in more.
The simulations show the importance of social media in recruiting people for a cause — whether it is finding balloons or finding a missing child. "It is simply impossible to do this without the ability to broadcast to all of your acquaintances ― something that is very easy using sites like Facebook and Twitter," Rahwan said.
But in order for social networks to be successful, they must be operating at the limit of their speed and efficiency, or the efforts run a risk of failure, he said.
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