Using Social Networks to Gather Information
In 2009, the Defense Advanced Research Projects Agency, or DARPA, created a challenge where they deployed 10 red weather balloons across the country, and teams competed to discover the locations of all the balloons. The grand prize was $40,000. The idea behind the challenge was to be able to take in massive amounts of information, and be able to filter out the truth from all of the false tips. To win, teams would need to rely on game theory and a good understanding of the behavior and properties of social networks.
Different teams used different approaches, some promising to donate the prize money to charities if they won, and others offering prizes to the first people to submit the correct locations. However, the team that won the competition, a mere 9 hours after it began, was the MIT team. Their strategy was to create a reward system that not only payed the person who sent in a correct balloon location, but also the person who referred that person, and the person who referred that person, so on. For each balloon, the $4000 was divided so that the person who found the balloon got $2000, the person who invited that person got $1000, then $500, then $250, and the remaining $250 was given to charity.
This approach relates to the 6 degrees of separation we looked at in class. Let’s say everyone on the MIT tells all their friends about the contest (a reasonable assumption, as they would want to maximize awareness about their cause to increase their chances of winning). Then those people have an incentive to tell their friends too, because if within 4 referrals, someone finds a balloon, the person at the beginning of the chain still gets paid. Within 4 degrees of separation from the MIT team, there would have been people in every part of the country, and they would all have an incentive to tell the truth about the balloons’ locations. This is what allowed the MIT team to find all of the balloons so quickly and efficiently. All it took was a little ingenuity and the power of networks.
http://www.popsci.com/technology/article/2009-12/how-mit-mobilized-social-networks-win-nationwide-hunt-10-red-balloons