Danko Georgiev, English Language Wikipedia, under GNU Free Documentation License

Wikipedia's remarkable accuracy and usefulness comes from something larger than the sum of its written contributions, a new study by SFI Research Fellow Simon DeDeo finds.

Read the article in Newsweek's The Daily Beast (April 29, 2013)

The free, anonymously written and edited online encyclopedia was widely expected to fall prey to cranks and partisans. Instead, it has proven no less accurate than the venerable Encyclopedia Britannica, according to several analyses of the quality of its information.

“The question is how?” asks DeDeo, who has studied the 11-year-old online knowledge repository as the product of a particularly cooperative human social system. “Wikipedia is an extremely high-functioning system. How do people create societies that have extremely high cooperation?”

A great example of this cooperative nature is Wikipedia’s article on former U.S. President George W. Bush – a highly contested piece of Wiki real estate that has been edited some 45,000 times.

“Show me a place on the Internet where people agree about George W. Bush?” asks DeDeo. “But the Wikipedia article reads as if it was written by aliens who didn't care [about Bush] – although we know it was written by people who cared a lot.”

Just how Wikipedia manages this collective balance is something DeDeo was able to study in detail because, unlike most other social systems, every Wikipedia edit is recorded.

“It's almost like you had closed circuit cameras running as a society is creating itself,” he says, “so every move could be studied and watched.”

All these sequences of behaviors create what can be viewed as a historical grammar, like that of a language or even bird song. A bird song, for example, has very simple grammar, with few elements and combinations possible – what's called a finite-state system. The historical language that creates and maintains Wikipedia might be expected to follow a rather limited grammar as well, but that's not what DeDeo discovered.

“The big result is that the Wikipedia behavior is what we call non-finite state,” DeDeo says. “It’s constantly generating new patterns of behavior that haven’t been seen before.”

One possibility, he says, is that the unbounded source for these behavior patterns in Wikipedia is shared between people – it’s the product of everyone’s mind. “That's what's really exciting,” he says.

Read DeDeo’s paper on Arxiv (December 18, 2012)

Read the article in Phys.org (March 27, 2013)