Minimum adjustment-based consistency and consensus models for group decision making with interval pairwise comparison matrices

Consistency and consensus play an important role in group decision making based on pairwise comparison matrices. In this paper, both the consistency and consensus issues for group decision making with interval pairwise comparison matrices are investigated. First, two minimum adjustment-based consistency improving models are proposed to simplify and improve the consistency improving model developed in a recent paper. Subsequently, to help decision makers reach consensus in group decision making, the group consensus degree is defined and then two minimum adjustment-based consensus reaching models are also developed, in which both the consistency and consensus issues are considered. It is also pointed out that the proposed consensus reaching model can generalize the consistency improving model. Through the proposed models, the consistency and consensus level for the interval pairwise comparison matrices can be improved, which will be helpful for deriving satisfactory and reasonable decision results in group decision making problems. Eventually, two numerical examples are provided to demonstrate the effectiveness of the proposed models.