A Modified Consensus-Building Methodology for Reaching a Group Decision Using Minimum Costs

This paper presents a methodology for building a consensus among the stakeholders based on the level of importance of each evaluation criterion to choose the best final design, approach, or solution for a project. The proposed methodology adopts an improved vague set minimum-cost consensus model (MCCM) and a modified Delphi method. This paper discusses several shortcomings of the traditional MCCM and the Delphi method. It argues that humans' resistance to change based on a numerical rating scale follows a natural logarithm pattern instead of a linear or quadratic pattern as claimed in other studies. Hence, the traditional MCCM needs to be revised accordingly. In addition, an experiment was concluded to compare the proposed consensus-building methodology with the traditional Delphi method. The experiment showed that the proposed methodology is better than the traditional Delphi method regarding using fewer rounds to reach a consensus. At last, this paper applies the proposed methodology to the field of road junction design selection.