Wikipedia is an online encyclopedia where articles may be written or edited by any user who creates a free account. It offers a vast amount of easily accessible information; the English version contained more than 1.7 million articles as of April 2007. But it can't guarantee accuracy and sometimes has been dramatically wrong.

 

Individuals who write and edit articles for Wikipedia are volunteers. In theory, they bring a vast collective knowledge to bear and quickly discover and correct any biased or inaccurate entries. Advocates say this bottom-up approach produces a product that rivals traditional, top-down encyclopedias in which articles are written by individual experts chosen by professional editors. Indeed, a study in the December 15, 2005, journal Nature reported that in a sample of 42 entries on scientific topics its experts found 162 errors in Wikipedia compared with 123 errors in Britannica. However, Britannica later challenged the Nature study as "fatally flawed" and filled with "flagrant errors."

 

The weakness of Wikipedia's anybody-can-edit policy was demonstrated dramatically when a false biographical entry on John Seigenthaler Sr., former editorial director of USA Today, went uncorrected for four months in 2005. It claimed Seigenthaler had a role in the assassinations of former President John Kennedy and his brother Robert. Those false claims were the work of a 38-year-old employee of a Nashville delivery service, Brian Chase, who had posted the libels as a joke and who later apologized to Seigenthaler. Numerous other instances of false Wikipedia entries have come to light since.

 

Wikipedia's own founder, Jimmy Wales, publicly cautions students against citing it as an authoritative source. In June 2006, at a conference sponsored by the Annenberg Public Policy Center of the University of Pennsylvania, he said that he gets about 10 e-mails a week saying, "Please help me. I got an F on my paper because I cited Wikipedia." Wales said those comments make him think to himself: “For God sake, you’re in college; don’t cite the encyclopedia.”

 

Wikipedia is "pretty good," Wales said, "but you have to be careful with it. It’s good enough knowledge, depending on what your purpose is.”