Two and three term representations of intuitionistic fuzzy sets: Some conceptual and analytic aspects

In the paper we revisit, and further analyze the concepts of two possible representations of Atanassov´s intuitionistic fuzzy sets´ (A-IFSs, for short): the two term one, in which the degrees of membership and non-membership are only involved, and the three term one, in which in addition to the above degrees of membership and non-membership the so called hesitation margin is explicitly accounted for. Though both representations are mathematically correct and may be considered equivalent, the second one involves explicitly an additional information. We show on examples of some decision making type problems its intuitive appeal and usefulness for reflecting more sophisticated intentions and preferences of the user.