Dynamic division of trust grade based on interval-valued fuzzy sets theory

Interval-value fuzzy sets theory is introduced to descript subjective trust quantitatively, and how to create the fuzzy trust model is solved. Based on the theory of interval-value fuzzy clustering, the paper proposes dynamic division of trust grade. The operation of the new method is as followed: firstly, get each interval-value of every element in the classification set, after that, turn the interval into [0, 1]; secondly, based on the first step, try to get the similarity of intervals directly; third, aggregation. The advantage of this method is that the interval value of every element can express the element more accurately and retain more information, which provides the basis of trust evaluation between entities.