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On an estimate of the rate of convergence in the central limit theorem in a Hilbert space. (English. Russian original) Zbl 0533.60029
Sov. Math., Dokl. 26, 575-578 (1982); translation from Dokl. Akad. Nauk SSSR 267, 276-279 (1982).
Let $$X_ j$$, $$j=1,2,..$$. be a sequence of i.i.d. random variables with values in a separable Hilbert space H. Assume that $$EX_ 1=0$$ and $$E\| X_ 1\|^{3+p}<\infty$$, $$0\leq p<1$$. Let $$\gamma$$ be an H- valued Gaussian random variable with mean 0 and the same covariance operator as $$X_ 1$$. The author proves that for all $$r\geq 0$$ $\sup \left| P \left( \| n^{-1/2} \sum^{n}_{j=1} X_ j \|< r \right) - P \left( \| \gamma \|<r \right) \right| = o\left(n^{-(1+p)/2}\right)$ as $$n\to\infty$$. An example shows that this rate of convergence is typical only for balls about zero.
Reviewer: R.Wegmann
##### MSC:
 60F05 Central limit and other weak theorems 60B12 Limit theorems for vector-valued random variables (infinite-dimensional case) 41A25 Rate of convergence, degree of approximation 60G50 Sums of independent random variables; random walks
##### Keywords:
covariance operator; rate of convergence