Variance Formulas for Trapezoidal Fuzzy Random Variables∗
نویسندگان
چکیده
The variance of fuzzy random variables often appears in fuzzy random programming problems. Based on the definition of the variance of a fuzzy random variable, this paper attempts to deduce several formulas for the variances of trapezoidal fuzzy random variables, in which the randomness is characterized by uniform distribution. Firstly, we give the moment formulas for trapezoidal fuzzy variables. Then, according to the obtained results, we deduce the variance formulas for trapezoidal fuzzy random variables. The obtained formulas are useful in studying the properties of fuzzy random programming problems. At last, we also provide some applications of the obtained formulas through three numerical examples. c ©2009 World Academic Press, UK. All rights reserved.
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