On the manipulability of the fuzzy social choice functions

In the social decision making context, a manipulator attempts to change the social choice in his favor by misrepresenting his preferences. Gibbard and Satterthwaite [7,10] established independently that a strategic manipulation can be observed when using any non-dictatorial voting choice procedure. In this paper, we are interested in the manipulation of the social choice when individuals reveal their preferences as fuzzy binary relations on the set of the alternatives. We address three ways for an individual to obtain the best set of alternatives with respect to his fuzzy preference relation. In each case, we define and prove the manipulability of non-dictatorial fuzzy social choice functions for a fuzzy individual relation domain.