Retrieval from uncertain data bases

Abstract

We investigate tools that can enrich the process of querying databases. We show how to include soft conditions with the use of fuzzy sets. We describe some techniques for aggregating the satisfactions of the individual conditions based on the inclusion of importance and the use of the OWA operator. We discuss a method for aggregating the individual satisfactions that can model a lexicographic relation between the individual requirements. We look at querying databases in which the information in the database can have some probabilistic uncertainty.