Approximate reasoning

  • Ernest Czogała
  • Jacek Łęski
Part of the Studies in Fuzziness and Soft Computing book series (STUDFUZZ, volume 47)


A fuzzy conditional statement (or conditional rule, or fuzzy if-then rule) assumes the form:
$$IF X is A THEN y is B,$$
where A and B are linguistic values of linguistic variables X and Y, defined by fuzzy sets A and B, respectively. Proposition “X is A” is called the premise or antecedent, and “Y is B” is called conclusion or consequence. In classical logic the statement “if P then Q” is written with implication PQ. Implication is a connective defined by Table 2.1.


Membership Function Fuzzy Relation Aggregation Operation Inference Result Fuzzy Rule Base 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Physica-Verlag Heidelberg 2000

Authors and Affiliations

  • Ernest Czogała
    • 1
  • Jacek Łęski
    • 1
  1. 1.Institute of ElectronicsSilesian University of TechnologyGliwicePoland

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