E(X) and the Equality of Expectation: Debunked or Confirmed?

Thread starter torquerotates
Start date Nov 8, 2014

Nov 8, 2014

torquerotates

Is this true? In all cases?

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Nov 8, 2014

WendyE

E(X) = expectation of X

Let X = {-1, 0, 1}
E(X) = (-1+0+1)/3 = 0

E|X| = ( |-1|+|0|+|1| )/3 = (1+0+1)/3 = 2/3

So, I think no, it's not true that E|X| = E(X) if I understand the question correctly.

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