Reducing information systems with uncertain attributes

  • Marzena Kryszkiewicz
  • Henryk Rybiński
Communications Session 3A Intelligent Information Systems
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1079)


We present Rough Set approach to reasoning in information systems with uncertain attributes. A similarity relation between objects is introduced. The relation is a tolerance relation. A reduction of knowledge we propose eliminates only information, which is not essential from the point of view of classification. Our approach is general in the sense it does not assume anything about the semantics of null values and uncertain multivalued attributes. We show how to find decision rules, which have minimal number of conditions and do not increase the degree of non-determinism of the original decision table.

Key words

Approximate Reasoning Knowledge Discovery Rough Sets Uncertain Information System Knowledge Representation Reduction 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Marzena Kryszkiewicz
    • 1
  • Henryk Rybiński
    • 1
  1. 1.Institute of Computer ScienceWarsaw University of TechnologyWarsawPoland

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