Augmenting a characterization network with semantic information

A searcher in a list of phrases which serves as an index to a set of documents often has problems nding the right words when the information sought for has to be described. O ering alternative phrasings and pointing to related concepts in the index could be a great help in this di cult process of query formulation. Usually the index is obtained by characterizing the set of documents. This paper examines the e ect of adding semantic relations to the index. Various ways in which nodes in an index can be related are discussed, and criteria for adding new index entries are introduced. The e ects of adding relations on the process of o ering support during the formulation process are treated as well. Constructing a representation of the information need can be done in many ways. In this paper we adopt a process called Query by Navigation. A searcher can use this process in order to browse an index, selecting relevant items along the way.