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The Limitations Of Crowdsourcing: On The Hunt For The Boston Bombers

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The finish line of the Boston Marathon, just after the explosion.
Some on Web sites in the hours and days following the Boston Marathon bombings drew conclusions based on photos and inferences that turned out to be incorrect.

Shortly after the Boston Marathon tragedy on April 15, the name "Sunil Tripathi" began circulating on the Internet as being suspected of involvement in the bombing.

The Brown University student — who had been missing without a trace since March 16 — was identified by users of Web sites Reddit and 4chan as resembling one of the photos the FBI had just released of the suspected bombers.

"Is missing Sunil Tripathi Marathon Bomber #2?" asked the Redditor known as "pizzatime."

Instantly, the comments went viral. Twitter was soon ablaze with tweets about having heard Tripathi’s name mentioned in connection with the bombing investigation, and his family was forced to temporarily freeze its "Help Us Find Sunil Tripathi" Facebook page after a flurry of harsh posts began arriving.

We know now that Tripathi was not involved at all in the bombings. In fact, eight days later, on April 23, his body was discovered in the waters off Providence, RI. It had been in the water for some time.

However, the damage to Tripathi’s reputation had been done.

"What we have here is a ‘Where’s Waldo?’ type of crowdsourcing gone bad," says Daren C. Brabham, an assistant professor at the University of North Carolina at Chapel Hill and a consultant on crowdsourcing.

Crowdsourcing, which is often used to obtain content by soliciting contributions from a large group of people, should be "a blend of top-down and bottom-up activity," explains Brabham. In this case, he says, "it was all bottom-up – the online community self-organizing and out for some kind of modern-day vigilante justice. That’s very different from the top-down structure the FBI uses when it goes out and does an investigation."

The FBI had been requesting people send them any lead that would help its efforts — and it was soon flooded with content, some of which eventually led to finding the perpetrators.

Less effective, says Brabham, were the Reddit and 4chan communities, "who were just latching on to any photo that made it onto the Web and doing their own investigative work, making up their own rules as they went along. It quickly devolved into kind of a witch-hunt."

According to Brabham, the problem was the result of the two communities not having sufficient guidance.

Yet Erik Martin is not surprised about the lack of guidance. As the general manager of Reddit, he says that is exactly how his Website functions – as a 2013 version of classic message boards, Usenet, or Internet Relay Chat (IRC).

"Reddit is a very minimal platform where anyone can come on and create a category – or subreddit – about practically any topic," Martin explains. "They can then moderate the content that other users post if they want. Some do, some don’t."

Whenever there is a big event in the world, whether it be a shooting in Aurora, CO, or a natural disaster like Hurricane Sandy or the tornados in Oklahoma, people create subreddits "to do all the things that people do after tragedies," says Martin. "In this case, subreddits focused on how to donate to victims, which Boston streets were open, whether flights were taking off, and other pieces of information – none of which was under the control of Reddit management."

Nevertheless, Martin apologized publicly for the mis-identification of Tripathi as being involved in the Boston tragedy.

However, he maintains, it would be wrong to jump to any conclusions about crowdsourcing based on this single incident – nor does he call it crowdsourcing "when a bunch of different people connected online try to contribute to something or to discuss something. Just because there’s a crowd doesn’t necessarily mean it is crowdsourcing."

"What this illustrated was that, in situations where there’s a lot of tension, rumors, and false information and half-information can be very problematic," Martin says. "I’m sure there are some technical ways this can be handled in the future, but the most important thing is that everyone needs to be aware of the impact mentioning someone’s name can have, especially in extreme cases like what happened in Boston."

The problem is not with crowdsourcing, but with the fact that crowdsourcing is not designed to fight crime, which should be left to professionals, says Luis von Ahn, an associate professor in the Computer Science Dept. at Carnegie Mellon University and a crowdsourcing expert.

Similarly, crowdsourced news can accomplish many things that news covered by professionals cannoy do, because there are so many more people than there are reporters, von Ahn says. However, he points out that few people in the crowd are trained to cover news, so they may not check all their facts the way professionals are taught to do.

"Because we have freedom of expression, I could post a blog saying that I think the bomber is my neighbor," he says. "The burden needs to be on the reader to take things on the Internet with a grain of salt if the information is coming from random or unprofessional sources."

Brabham’s best advice is to do some emergency preparedness now, rather than later. He strongly suggests the police or the FBI set up a "dark site" – a platform to be activated in time of need to solicit leads from private citizens, which is governed by a clear set of rules. That way, the next time a public emergency arises, the news media can tell people immediately that if they have any information to contribute, they need to go to, say, BostonBombing.FBI.gov, for example, and nowhere else.

"There is no way you can regulate or control crowdsourcing, nor should there be," Brabham says. "But if the vast majority of the public knows there exists an official place where they can assist, I think it would limit the sort of free-for-all we’ve just seen."

Paul Hyman is a science and technology writer based in Great Neck, NY.

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