For a user who is unfamiliar with a target domain, the first step to conduct an exploratory search task is to go over a learning phrase, which means to learn from the search results to acquire basic domain knowledge. Since lots of search results could be returned by a search engine, and usually...

Social tagging is one of the most important ways to organize and index online resources. Recommendation in social tagging systems, e.g. tag recommendation, item recommendation and user recommendation, is used to improve the quality of tags and to ease the tagging or searching process. Existing...