MULTIPLE CRITERIA DECISION-MAKING MODELS IN GROUP DECISION-SUPPORT

Use of multiple criteria decision making (MCDM) models to aid the grou p decision process was tested. Two multiple criteria group decision su pport systems (MCGDSS) were studied, one using the AHP:Tchebycheff met hod of Iz and the other using Kersten's NEGO system. These systems wer e compared with a commercial GDSS, VisionQuest. VisionQuest does not i nclude multiple criteria tools. To make the study comparable, VisionQu est was augmented with an ad hoc linear programming model that could g enerate solutions with specified characteristics requested by the usin g group. The three systems were compared on the dimensions of solution quality and decision support effectiveness. One of the hypotheses was that MCDM models would force participants to examine criteria, prefer ences, and aspirations more thoroughly, thus leading to decisions of b etter quality. Subjects using the MCGDSSs were expected to have higher mean quality and effectiveness values. However, the quality and effec tiveness values of the VisionQuest/ad hoc system were found to be bett er on the dimension of effectiveness. Explanations for this result are included in the paper.Another hypothesis was that the AHP/Tchebycheff method of Iz, a value-oriented system, would yield more effective gro up support than the goal-oriented NEGO system. However, the NEGO syste m was found to yield solutions with better quality measures than the s olutions obtained with the AHP/Tchebycheff system. Observation of the groups using the MCDM systems indicate that both the AHP/Tchebycheff a nd NEGO methods can be revised to enhance their effectiveness. The pri mary difficulty encountered with the AHP/Tchebycheff method was in the large number of pairwise comparisons required by AHP. The NEGO method can be enhanced by including specification of desired attainment leve ls in the first stage of the method. Both MCDM techniques have potenti al to benefit group decision support by giving using groups a means to design better solutions.