Opinion Dynamic Under Malicious Agent Influence in Multi-Agent Systems: From the Perspective of Opinion Evolution Cost

In human social systems, debates are often seen as a means to resolve differences of opinion. However, in reality, debates frequently incur significant communication costs, especially when dealing with stubborn opponents. Inspired by this phenomenon, this paper examines the impact of malicious agents on the evolution of normal agents' opinions from the perspective of opinion evolution cost, and proposes corresponding solutions for the scenario in which malicious agents hold different opinions in multi-agent systems(MASs). First, this paper analyzes the negative impact of malicious agents on the opinion evolution process, reveals the additional evolution cost it brings, and provides a theoretical basis for the subsequent solutions. Secondly, based on the characteristics of opinion evolution, the malicious agent isolation algorithm based on opinion evolution direction vector is proposed, which does not strongly restrict the proportion of malicious agents. Additionally, an evolution rate adjustment mechanism is introduced, allowing the system to flexibly regulate the evolution process in complex situations, effectively achieving the trade-off between opinion evolution rate and cost. Extensive numerical simulations demonstrate that the algorithm can effectively eliminate the negative influence of malicious agents and achieve a balance between opinion evolution costs and convergence speed.