Let X be a discrete random variable with range {1,2,...,n} so that its pmf is given by px(j) = 1/n for 1<= j <= n. Use the MGF to find E(X) and V(X).
I came up with sum 1 to n of (1/n)e^(t/n) for the MGF. Taking the derivative and setting t = 0 gives me sum 1 to n of 1/n^2. Have I done this incorrectly?
I came up with sum 1 to n of (1/n)e^(t/n) for the MGF. Taking the derivative and setting t = 0 gives me sum 1 to n of 1/n^2. Have I done this incorrectly?
Finan 49.1
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