Computer-supported collaborative argumentation and fuzzy similarity measures in multiple criteria decision making

Abstract Group decision making is usually performed in the presence of conflicting goals and criteria, brought up by spatially dispersed parties with different backgrounds and interests. Recent advances in information technology and computer science may satisfactorily address a variety of related problems, such as communication among the decision makers and efficient elicitation and representation of the domain knowledge. Furthermore, they may significantly automate the decision making process itself. On the other hand, the inherent uncertainty of the problem advocates the use of approximation models, often coming from the fuzzy sets discipline. This paper presents an integrated framework for multiple criteria decision making among groups on the World Wide Web. The agents involved use a fully implemented argumentative discourse system to pursue their criteria and objectives, the aim being the specification of the desired solution to the problem. The system organizes the collective knowledge in a discussion graph with truth maintenance and consistency checking features. Fuzzy similarity measures are then involved in order to assess alternative existing solutions with respect to the desired one. Scope and purpose We view multiple criteria decision making as a collaborative process, where decision makers have to follow a series of communicative actions in order to establish a common belief on the dimensions of the problem. Such dimensions may concern the choice criteria, the existing or desired alternative solutions, or the objective function, to mention some. This paper presents a framework for multiple criteria decision making among groups. Our approach exploits recent advances in information technology and manages to (i) remove the communication impediments among spatially dispersed decision makers, (ii) efficiently represent the domain knowledge, (iii) develop efficient mechanisms to structure and consistently maintain the decision analysis, and (iv) automate the multiple criteria decision making process per se. The framework is based on a fully implemented system, namely H ermes , which enhances decision making by supporting argumentative discourse among decision makers. The system is implemented in Java and runs on the World Wide Web, thus providing relatively inexpensive access to a broad public.