With the advent of Web 2.0 technologies a new attitude towards processing contents in the Internet has emerged. Nowadays it is a lot easier to create, share and retrieve multimedia contents on the Web. However, with the increasing amount in contents the retrieval process becomes more complex and...

One potential disadvantage of social tagging systems is that due to the lack of a centralized vocabulary users may never manage to reach a consensus on the description of the entities (e.g., books, user or songs) in the system. Yet, previous research has provided interesting evidence that the...