Extended Fuzzy Sets and Their Applications Farhadinia, Bahram Chiclana Parrilla, Francisco Fuzzy set (FS) Intuitionistic fuzzy set (IFS) Pythagorean fuzzy set (PFS) P-rung orthopair fuzzy set (p-ROFS) Extended fuzzy set (E-FS) Decision making This contribution deals with introducing the innovative concept of extended fuzzy set (E-FS), in which the S-norm function of membership and non-membership grades is less than or equal to one. The proposed concept not only encompasses the concept of the fuzzy set (FS), but it also includes the concepts of the intuitionistic fuzzy set (IFS), the Pythagorean fuzzy set (PFS) and the p-rung orthopair fuzzy set (p-ROFS). In order to explore the features of the E-FS concept, set and algebraic operations on E-FSs, average and geometric operations of E-FSs are studied and an E-FS score function is defined. The superiority of the E-FS concept is further confirmed with a score-based decision making technique in which the concepts of FS, IFS, PFS and p-ROFS do not make sense. 2021-05-25T07:08:37Z 2021-05-25T07:08:37Z 2021-04-02 journal article Farhadinia, B.; Chiclana, F. Extended Fuzzy Sets and Their Applications. Mathematics 2021, 9, 770. [https://doi.org/10.3390/math9070770] http://hdl.handle.net/10481/68692 10.3390/math9070770 eng http://creativecommons.org/licenses/by/3.0/es/ open access AtribuciĆ³n 3.0 EspaƱa MDPI