An Overview of Information Retrieval Subjects

The aim of an information retrieval system is to find information items relevant to an information need. As relevance is a kind of similarity relation between the concepts represented by the information item and those represented by the formulation of the information need, it is not astonishing to discover that the class of possible query forms -formulations of the information needs - is the same as the class of possible representations of information items. This article overviews current research problems in information structure and query evaluation