- University of Duisburg
- Information Retrieval Group (IR group at LTI/CMU)
- Oracle UltraSearch
Information Retrieval is the process of locating information that fits a user's information need, which is usually expressed as a search query. The fit of the retrieved information with the information need is referred to as "relevance". The information can be retrieved from databases (data retrieval) or from document collections (document retrieval), where documents can either be text documents or other media (audio, video, semi-structured data, multimedia). Success in information retrieval is generally defined by retrieving as much relevant information as possible (measured by "recall") while minimising the irrelevant information retrieved (measured by "precision"). The most widely used information retrieval systems today are Internet search engines.