Indirect reciprocity is an important factor that motivates individual contributions in social networks. However, prior studies of indirect reciprocity are often limited to a snapshot view of individual interactions in social environments. This paper analyzes indirect reciprocity from a dynamic...

The long tail phenomenon has been attributed to both supply side and demand side economies. While the cause on the supply side is well-known, research on the demand side has largely focused on the awareness effect of online information that helps consumers discover new and often niche products....

This study examines the incentives for content contribution in social media. We propose that exposure and reputation are the major incentives for contributors. Besides, as more and more social media Web sites offer advertising-revenue sharing with some of their contributors, shared revenue...