Fuzzy Set Theory-Based Trust Models in Multi-Agent Environment

Trust mechanism is the key foundation to ensure the security in multi-agent environments. In view of the shortcomings in the existing models, we develop a valuable evaluation mechanism using fuzzy set theory to describe its trust models in this paper. A multiple-attribute fuzzy decision is introduced so that the trust evaluation is more consistent with the thinking custom in the human society. In our trust recommendation, we present similarity techniques based on the coefficients of rating-attribute weight so that the trust values are more accordant with subjectivity, and introduce a lattice measure of similarity that can effectively diminish the influence from some malicious recommendations. Meanwhile, our model improves the derivation rules of trust recommendation relationships by multiple multivariable fuzzy reasoning mode and fuzzy uncertainty reasoning theory. Subsequent experimental results show that our model can inhibit malicious transactions more effectively than Eigen Trust, and thus give a significant way for studying the security mechanism in multi-agent environments.