Edgeworth Expansions for Integrals of Smooth Functions

Abstract

Let $X_1, X_2,\cdots$ be a sequence of independent, identically distributed random variables with $E(X_1) = 0, E(X_1^2) = 1$, and $E(X_1^4) < \infty$, and for $n = 1,2,\cdots$ let $P_n$ be the distribution of $n^-\frac{1}{2} \sum^n_{i=1} X_i$. If $f$ is a function with bounded uniformly continuous derivative of order 4, then $\int f dP_n$ has an asymptotic expansion in terms of $n^{-\frac{1}{2}}$ with a remainder term of $o(n^{-1})$. This remains true even if $P_1$ is purely discrete and nonlattice.