Platforms operators act as private regulators to increase usage and maximize profits. Their goals depend on the development of the platform: overcoming the chicken-egg problem early on requires attracting platform participants while quality becomes more important later on. Private regulators...

Today Online Social Networks (OSN) are very popular Web sites which show remarkable user growth and attention on the Internet. One reason of the extraordinary success of these social software sites are the enhanced Web 2.0 technologies and concepts, but they do not really explain why a OSN in...