{{% hassett_navigation %}} [TOC] Sections 6.1, 6.2.1 only # 6.1 Functions of random variables and their expectations In general, the expectation value of $f(x)$ is $$ E(f(x)) = \sum f(x) p(x) $$ An example about expected utility of wealth rather than just wealth. A proof that $V(X)=E(X^2)-(E(X))^2$. # 6.2.1 Moments of a random variable The expectation value of some power of $X$, $E(X^n)$, is called the $n$-th moment of the distribution.