Hugh Pickens writes "Yoni Appelbaum reports in the Atlantic that as part of their coursework in a class that studies historical hoaxes, undergraduates at George Mason University successfully fooled Wikipedia's community of editors, launching a Wikipedia page detailing the exploits of a fictitious 19th-century serial killer named Joe Scafe. The students, enrolled in T. Mills Kelly's course, Lying About the Past, used newspaper databases to identify four actual women murdered in New York City from 1895 to 1897, along with victims of broadly similar crimes, and created Wikipedia articles for the victims, carefully following the rules of the site. But while a similar page created previously by Kelly's students went undetected for years, when students posted the story to Reddit, it took just twenty-six minutes for a redditor to call foul, noting the Wikipedia entries' recent vintage and others were quick to pile on, deconstructing the entire tale. Why did the hoaxes succeed in 2008 on Wikipedia and not in 2012 on Reddit? According to Appelbaum, the answer lies in the structure of the Internet's various communities. 'Wikipedia has a weak community, but centralizes the exchange of information. It has a small number of extremely active editors, but participation is declining, and most users feel little ownership of the content. And although everyone views the same information, edits take place on a separate page, and discussions of reliability on another, insulating ordinary users from any doubts that might be expressed,' writes Appelbaum. 'Reddit, by contrast, builds its strong community around the centralized exchange of information. Discussion isn't a separate activity but the sine qua non of the site. If there's a simple lesson in all of this, it's that hoaxes tend to thrive in communities which exhibit high levels of trust. But on the Internet, where identities are malleable and uncertain, we all might be well advised to err on the side of skepticism (PDF).""