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Let X1,…,XnX_1,\ldots,X_n be independent real random variables with EXi=0\mathbb EX_i=0, finite ρi=E∣Xi∣3\rho_i=\mathbb E|X_i|^3, and total variance V=∑iEXi2>0V=\sum_i\mathbb EX_i^2>0. If Φ\Phi is the standard normal distribution function, then for an absolute constant CC,

sup⁡t∈R∣Pr⁡(V−1/2∑iXi≤t)−Φ(t)∣≤C∑iρiV3/2.\sup_{t\in\mathbb R} \left|\Pr\left(V^{-1/2}\sum_iX_i\le t\right)-\Phi(t)\right| \le C\frac{\sum_i\rho_i}{V^{3/2}}.

This is an external statement, not a proof reconstructed here. The paper cites Berry (1941), Esseen (1942), and Shevtsova (2010); it does not need a particular numerical value of CC. The condition V>0V>0 is stated explicitly because the normalized variable is otherwise undefined.

The local moment calculation verifies every hypothesis, including uniformity after removing one coordinate, in the application.

Source: published PDF, p. 4, Lemma 3; earlier v1 p. 3, Lemma 4.

Bears on. Problem 297.