Fuzzy truth values in option prioritization for preference elicitation in the Graph Model

A methodology is developed to use the fuzzy truth values of preference statements for feasible states in an option prioritization technique in order to rank states within the framework of the Graph Model for Conflict Resolution. Option prioritization ranks states based on the truth values of preference statements, which are compositions of the decision makers´ courses of actions joined by logical connectives, ordered lexicographically. Fuzzy truth values are represented as truth degrees; so they include binary truth values, “true” and “false”, as well as other possible truth intensities that are reasonable according to the specific circumstances. Consequently, the assumption of fuzzy truth values of preference statements provides more realistic preference ordering of feasible states. The methodology is applied to the Elmira groundwater contamination dispute, which took place in Elmira, Ontario, Canada, for eliciting the preferences of decision makers, to demonstrate the applicability of this technique.