Trust Improvement Consensus Model Considering Unreliability Degree of Opinions with Hesitant Fuzzy Sets

Abstract

Trust is a crucial element in the consensus decision-making process, as it significantly impacts a group’s capacity to achieve consensus. Nevertheless, low trust by experts may result in detrimental decision-making behaviors that decrease group consensus degree. Meanwhile, it is important to note that experts’ opinions are not always reliable, and ignoring the unreliability degree of opinions may have an impact on the result of consensus decision-making. To deal with these issues, this paper proposes a trust improvement consensus model considering unreliability degree of opinions. First, considering that the discreteness of membership degree has a much smaller impact on the hesitancy degree in hesitant fuzzy elements than the number of membership degrees in extant research, an improved approach is suggested to quantify the unreliability degree of opinions. Second, a trust improvement method is proposed based on the score function for trust propagation path and the trust propagation operator considering unreliability degree of opinions. Third, a method for adjusting the opinions of experts is suggested, considering unreliability degree of opinions. Finally, the feasibility, effectiveness, and advantages of the proposed trust improvement consensus model are verified through a case study on the selection of cascade utilization alternatives for power lithium-ion batteries, as well as simulation and comparative analysis. The results show that: (1) The improved method exhibits a significant impact of the discreteness of membership degree on the hesitancy degree; (2) Trust improvement can facilitate group consensus, and the score function of trust propagation path can enhance trust degree among experts more effectively; (3) The unreliability degree of opinions not only affects the degree of trust improvement but also affects the ranking of alternatives. By taking into account the unreliability degree of opinions throughout the process of adjusting opinions, it is possible to promote group consensus and decrease the unreliability degree of opinions.