For Generate Random Sample, the Beta distribution can be defined by its **Mean** and **Variance** or by two shape parameters a and b. The mean is equal to a(a+b)^{−1} with variance ab(a+b+1)^{−1}(a+b)^{−2};. By default, the two-parameter form is used, defined on the range (0,1). By setting the lower and upper bounds the four-parameter form can be used, defined on the specified range.

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**Specify parameters**to display the**Mean**and**Variance**fields.