arXivDaily arXiv每日学术速递 周一至周五更新
arXiv math/0611108math.STstat.TH
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大规模多重比较中方差和非方差比例的估计

Estimating the Null and the Proportion of non-Null effects in Large-scale Multiple Comparisons

Jiashun Jin, T. Tony Cai

摘要:

Efron在大规模多重比较的背景下提出的一个重要问题是,在许多应用中,通常假设零分布是已知的是不正确的,看似可以忽略的零差异可能会导致后续研究中的巨大差异。这表明,对零值的估计进行仔细的研究是必不可少的。在本文中,我们考虑零正态分布的估计问题,和一个密切相关的问题,估计的比例,非零效应。我们发展了一种基于经验特征函数和傅里叶分析的方法。估计是一致一致的,在广泛的一类参数。使用模拟和真实数据的估计的数值性能进行了研究。特别是,我们将我们的程序应用于乳腺癌和HIV微阵列数据集的分析。与现有方法相比,估计器表现良好。

英文摘要:

An important issue raised by Efron in the context of large-scale multiple comparisons is that in many applications the usual assumption that the null distribution is known is incorrect, and seemingly negligible differences in the null may result in large differences in subsequent studies. This suggests that a careful study of estimation of the null is indispensable. In this paper, we consider the problem of estimating a null normal distribution, and a closely related problem, estimation of the proportion of non-null effects. We develop an approach based on the empirical characteristic function and Fourier analysis. The estimators are shown to be uniformly consistent over a wide class of parameters. Numerical performance of the estimators is investigated using both simulated and real data. In particular, we apply our procedure to the analysis of breast cancer and HIV microarray data sets. The estimators perform favorably in comparison to existing methods.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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