In this paper we formulate the fuzzy bilevel programming problem and describe one possible approach for formulating a crisp optimization problem being attached to it. Due to the nature of fuzzy bilevel programming this is a crisp bilevel programming problem. We compare our approach with one using multicriterial optimization and show, that both approaches are basically different. The use of multicriterial optimization rests on reformulating the original problem into a multicriterial fuzzy optimization problem and thus in deleting the hierarchical structure of the problem.
Working paper September 2007, Department of Mathematics and Computer Science, Technical University Bergakademie Freiberg, Germany