期刊名称:Sankhya. Series A, mathematical statistics and probability
印刷版ISSN:0976-836X
电子版ISSN:0976-8378
出版年度:2008
卷号:70
期号:02
页码:186--222
出版社:Indian Statistical Institute
摘要:We give analytic methods for nonparametric bias reduction that remove the
need for computationally intensive methods like the bootstrap and the jack-
knife.
We call an estimate pth order if its bias has magnitude n.p
0 as n0 → ∞,
where n0 is the sample size (or the minimum sample size if the estimate is
a function of more than one sample). Most estimates are only first order
and require O(N) calculations, where N is the total sample size. The usual
bootstrap and jackknife estimates are second order but they are computa-
tionally intensive, requiring O(N2) calculations for one sample. By contrast
Jaeckel¡¯s infinitesimal jackknife is an analytic second order one sample es-
timate requiring only O(N) calculations. When pth order bootstrap and
jackknife estimates are available, they require O(Np) calculations, and so
become even more computationally intensive if one chooses p > 2.
For general p we provide analytic pth order nonparametric estimates that
require only O(N) calculations. Our estimates are given in terms of the
von Mises derivatives of the functional being estimated, evaluated at the
empirical distribution.
For products of moments an unbiased estimate exists: our form for this
¡°polykay¡± is much simpler than the usual form in terms of power sums.
关键词:Bias reduction; k¨Csamples; nonparametric; unbiased
estimate; U¨Cstatistics; Von Mises derivatives.