Abstract
This chapter examines type-reduction and direct defuzzification for interval type-2 fuzzy logic systems. It provides critiques of type-reduction as an end to itself as well as of direct defuzzification, and concludes that: (1) a good way to categorize type-reduction/direct defuzzification algorithm papers is as papers that either focus on algorithms that lead to a type-reduced set, or directly to a defuzzified value; (2) research on type-reduction as an end to itself has led to results that are arguably of very little value; and, (3) the practice of base-lining an IT2 FLS that uses direct defuzzification against one that uses type-reduction followed by defuzzification is unnecessary.
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Mendel, J.M. (2015). On Type-Reduction Versus Direct Defuzzification for Type-2 Fuzzy Logic Systems. In: Tamir, D., Rishe, N., Kandel, A. (eds) Fifty Years of Fuzzy Logic and its Applications. Studies in Fuzziness and Soft Computing, vol 326. Springer, Cham. https://doi.org/10.1007/978-3-319-19683-1_20
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