Fuzzy Database Model Based on Quasi-Order Relations

• Authors: R. Groenemans;E. Kerre;G. De Cooman;E. Van Ranst
• Venue: Journal of Intelligent Information Systems
• Year: 1997

As we live in an information era, the needfor gathering, storing and handling enormous amounts of data in apractical and economical way has become more and more important.Classical database systems were introduced in the late fifties and have proved their usefulnes in various domains. However, their inability to deal with vague and imprecise information has led to new database models. On the other hand the use of linguistic terms has also shown its usefulness in several domains. The assignment of linguistic terms to phenomena and the description of the characteristics, properties or conditions of objectsseems something very natural. People make such assessments every day. A drawback of using linguistic terms, however, is that these terms are not always sharply defined and moreover their meaning very often differs for different individuals.Thus, when different individuals consult the same database or information system, which uses such linguistic terms, these differences should somehow be taken into account, in order to avoid inconsistencies.These inconsistencies could have consequences on the decisions based on such data. In this paper we introduce a new database model based on quasi-order relations (reflexive and transitive). The proposed model describes the mathematical background of the assessment of values to database attributes, using the theory of evaluation problems and sets. The constructed model offers the possibility toreduce possible inconsistencies and presents an interesting new approachto the theory of database design and linguistic terms.