From the New York Times:
Do you like to share awe-inspiring articles with your friends, like the many Times readers whose habits are analyzed in a new study? Or do you have other motives?
In my Findings column, I describe a new analysis of The Times list of most-e-mailed articles by researchers at the University of Pennsylvania, Jonah Berger and Katherine A. Milkman. Dr. Berger, who has previously studied trends in naming children and the the spread of information on the Web, told me that the Timesâ€™ most e-mailed list provided a rare opportunity to observe the â€œviralityâ€ of different types of information.
Previous researchers have analyzed which nodes on social networks seem especially important in spreading, and there have been small-scale studies (like this 2002 study by researchers at Knox College) asking people what kinds of gossip they would pass. But The Timesâ€™ list offered a real-time look at which stories on the Web home page were being shared by thousands of people with their friends. The researchers controlled for factors like how long the article was promoted on the home page and exactly where on the page it appeared.