A Consensus Model to Manage Unavailability of Decision-Makers in Group Decision Making.

All the known Group Decision Making (GDM) models assume the continuous availability of all decision-makers (DMs) during the Consensus Reaching Process (CRP). Factually, the constant presence of a DM means that the concerned DMs are interested in adequately contributing to the decision-making process, and the technical support continuously enables their support. However, in a realistic situation, one or more DMs may be unavailable at times in CRP iterations due to technical or non-technical reasons. This paper considers such a scenario wherein the DMs are sparsely present. Hence, working out a model to take care of such pertinent absences that eventually make GDM possible. The bounded confidence of an individual DM is used to facilitate CRP in evaluating the opinions of the unavailable DMs. We propose to assign weight to a DM based on their cumulative presence in the decision process. Consideration of the opinion of a DM in a particular iteration based on the opinion in the previous iterations in case of the absence of the concerned DM in an implementation shown here is shown to be helpful.