Top-k Algorithms and Applications

In recent years, there has been a great deal of interest in developing effective techniques for ad-hoc search and retrieval in relational databases, document and multimedia databases, scientific information systems, and so on. A popular paradigm for tackling this problem is top-k querying, i.e., the rankinf of the results and returning the k results with the highest scores. Numerous variants of the top-k retrieval problem and several algorithms have been introduced in recent years. In this tutorial we shall discuss the top-k problem in detail, especially the fundamental algorithms such as FA and TA, important variants such as algorithms operating under restricted sorted/random access, deterministic and probabilistic approximations, as well as distributed and streaming top-k computations. A significant portion of the tutorial will be focused on applications of these top-k algorithms, especially in the context of the Web services and online databases, multimedia, documents and relational databases.