Consensus in Group Decision Making Under Linguistic Assessments

In this research, three new consensus measure methods have been developed for group decision making problem in this research. One is a Markov chain based consensus measure method, the other is order based, and the last one is a similarity based consensus measure approach. The Markov chain based method takes the advantage of the steady state property of the Markov chain to generate the ideal consensus matrix. By measuring the similarity between the current peer evaluation matrix and the ideal one, we have the consensus value. The order based method is to measure the group preference order rank of alternatives and the individual preference order. The difference indicates the consensus level. After measuring the current consensus, experts could modify their evaluations to 5 improve the consensus level. The cost analysis gives the least cost suggestion for this modification, as well as the least cost of the final consensus and the group decision making.