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:2011
卷号:73
期号:02
页码:267--302
出版社:Indian Statistical Institute
摘要:Dening a location parameter as a generalization of the median, a robust test is
proposed for (a) the nonparametric Behrens-Fisher problem, where the underlying
distributions may have di
erent scales and could be skewed, and (b) the generalized
Behrens-Fisher problem, where the distributions may even have di
erent shapes. We
propose to bootstrap a signed rank statistic based on di
erences of sample values
and derive rigorous bootstrap central limit theorems for its probabilistic justication,
allowing for the so-called m-out-of-n bootstrap. The location parameter of interest
is the pseudo-median of the distribution of the di
erence between a control measure-
ment and an observation from the treatment group. It reduces to (a) the shift in the
two sample location model and (b) the di
erence between the centers of symmetry in
the nonparametric Behrens-Fisher model, under the additional assumption that the
distributions are symmetric. Due to its importance for applications, we also extend
our results to an ANOVA design where each treatment is compared with the control
group. Finally, we compare our test with competitors on the basis of theory as well as
simulation studies. It turns out that our approach yields a substantial improvement
for distributions close to the generalized extreme value type, which makes it attrac-
tive for applications in engineering as well as nance. Several heteroscedastic data
sets from electrical engineering, astro physics, energy research, analytical chemistry
and psychology are used to illustrate our solution.
关键词:Bootstrap, central limit theorem, generalized extreme value
distribution, heteroscedasticity, signed-rank statistics, U-statistics.