A Cost Consensus Metric for Consensus Reaching Processes based on a comprehensive minimum cost model

Consensus Reaching Processes (CRPs) have recently acquired much more importance within Group Decision Making real-world problems because of the demand of either agreed or consensual solutions in such decision problems. Hence, many CRP models have been proposed in the specialized literature, but so far there is not any clear objective to evaluate their performance in order to choose the best CRP model. Therefore, this research aims at developing an objective metric based on the cost of modifying experts' opinions to evaluate CRPs in GDM problems. First, a new and comprehensive minimum cost consensus model that considers distance to global opinion and consensus degree is presented. This model obtains an optimal agreed solution with minimum cost but this solution is not dependent on experts' opinion evolution. Therefore, this optimal solution will be used to evaluate CRPs in which experts' opinion evolution is considered to achieve an agreed solution for the GDM. Eventually, a comparative performance analysis of different CRP5 on a GDM problem will be provided to show the utility and validity of this cost metric. (C) 2019 Elsevier B.V. All rights reserved.