# Question:Strange result when calculating Mean symbolically

## Question:Strange result when calculating Mean symbolically

Maple
I am trying to use the Mean command of the Statistics package to calculate the arithmetic mean of a transformed random variable symbolically. I am using Maple 10. In my case the Mean command gives an incorrect answer. First a simple example, which gives me a correct result symbolically: restart;with(Statistics): X:=RandomVariable(Uniform(-Pi, Pi)); Mean(X+a);#it gives a, it is ok. #and here is my more complicated problem: restart;with(Statistics):X:=RandomVariable(Uniform(-Pi, Pi)); assume(Gt::RealRange(Open(0),Open(1)),Gr::RealRange(Open(0),Open(1))); Mean(abs(1-Gt*Gr*exp(-I*X))); # it gives me -1 which is obviously incorrect, because of abs(). Originally I wanted to calculate the standard deviation of this expression, it gave me no result, then I just checked the more simple Mean calculation, but it also failed. Perhaps some integration problem? Thank you for any comment in advance.
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