Researches On The Individual Consistency And Group Consensus Of Best Worst Method

Best-Worst method(BWM)is a new multi-criteria decision-making method based on pairwise comparisons,but only the comparisons concerning the best and the worst alternatives or criteria.This method shows some significant advantages in the simplicity with a less requirement of comparison data and reliability with better consistency.This dissertation takes BWM as the research object and study it further from consistency and consensus two aspects.The main research results are as follows.This dissertation analyses the features of reference comparison vectors in BWM,we find the distance between the vectors of reference comparisons in BWM directly reflect the logicality of comparisons and affects the reliability of results,so it can be seen as an indicator of consistency.We propose a new consistency measure method based on the distance so we could easily measure the consistency of the comparisons given by decision maker before the solving of priority weights.Meanwhile,we also define the satisfactory consistency by establishing a more persuasive threshold of consistency ratio based on statistics.Two programming approach are given respectively to get interval weights for consistent and inconsistent comparisons.The current research which apply the BWM in group decision making mostly focus on the solving method,but this dissertation focuses on the consensus reaching process.We give a method to calculate the similarity of two groups of reference comparison vectors and define the individual consensus degree and group consensus degree by transform the vectors of reference comparisons into the form of preference relation.An iterative optimization algorithm is developed to adjust the comparisons with poor consensus to improve the overall consensus degree.In addition,we propose a priority weight solving method considering the consistency and individual consensus together for BWM group decision making.Finally,this dissertation studies the selection of sustainable furnishing materials.We apply the proposed method to the construction of evaluation index system and give the results analysis.