A method of measuring uncertainty for Z-number

Z-number is a new framework of fuzzy sets that combines with constraint and reliability. Managing the uncertainty of Z-number is an important issue in the fuzzy decision making of Z-number based. In this paper, we first develop a new uncertainty measure of fuzzy set considering the influence of fuzziness measure and the range (or cardinality) of the fuzzy set. Some properties of the developed uncertainty measure of the fuzzy set are presented. We then propose and discuss method of measuring the uncertainty of Z-number. Examples are used to illustrate the effectiveness of the proposed methodologies.