Statistical Inference by George Casella and Roger L. Berger)
Part 1: Moments
Definition 1 For each integer $n$, the nth moment of $X$, $\mu_n^{'}$ is
\[\mu_{n}^{'} = EX^n.\]
The nth central moment of $X$, $\mu_n$, is
\[ \mu_n = E(X-\mu)^n,\]
where $\