Group decision making: Suppositions and practice

TLDR: The results suggest that simple aggregation/consensus models are not satisfactory, and highlights the importance of approaching group decision making as a process that benefits from using models.

Abstract: This paper first contrasts issues in single and group decision making. It highlights the importance of approaching group decision making as a process that benefits from using models. Some key observations of decision support in real life applications are described, and the problems of combining individual preferences into a group choice are examined. This is followed by two case studies where judgemental models were used to support the decision process. In each example, the problem structure, the preferences of the individual decision makers, the overall decision process and the resulting decisions are given in detail. The cases provide insights into how groups use such judgemental information in discussion, negotiation, and the reaching of an agreement. Our results suggest that simple aggregation/consensus models are not satisfactory.