Of course we share! Testing Assumptions about Social Tagging Systems- A Study of User Behavior in BibSonomy

Social tagging systems have established themselves as an important part in today’s web and have attracted the interest of our research community in a variety of investigations. Henceforth, several assumptions about social tagging systems have emerged on which our community also builds their work. Yet, testing such assumptions has been difficult due to the absence of suitable usage data in the past. In this work, we thoroughly investigate and evaluate four assumptions about tagging systems – covering social, retrieval, equality, and popularity issues – by examining live server log data gathered from the real-world, public social tagging system BibSonomy. Our empirical results indicate that while some of these assumptions hold to a certain extent, other assumptions need to be reflected in a very critical light. Our observations have implications for the understanding of social tagging systems, and the way they are used in open environments.