A fuzzy rule based mechanism for ranking multiple information sources

In this paper the information retrieval activity from multiple sources of information is considered. A method is proposed to define a prototypal document for each information source as a second order fuzzy set; this document is seen as a representative of the contents dealt with in the documents of the collection and it is employed to evaluate the relevance of the information source to a given user's query. To this aim a fuzzy rule based query evaluation mechanism is defined.