From the Annals of Altruism, Wikipedia Again

A closer look at the Good Samaritans at Wikipedia (via EurekAlert):

Dartmouth researchers looked at the online encyclopedia Wikipedia to determine if the anonymous, infrequent contributors, the Good Samaritans, are as reliable as the people who update constantly and have a reputation to maintain.

The answer is, surprisingly, yes. The researchers discovered that Good Samaritans contribute high-quality content, as do the active, registered users. They examined Wikipedia authors and the quality of Wikipedia content as measured by how long and how much of it persisted before being changed or corrected.

"This finding was both novel and unexpected," says Denise Anthony, associate professor of sociology. "In traditional laboratory studies of collective goods, we don't include Good Samaritans, those people who just happen to pass by and contribute, because those carefully designed studies don't allow for outside actors. It took a real-life situation for us to recognize and appreciate the contributions of Good Samaritans to web content."