arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0908.1712math.STstat.TH
收藏

高维正态均值向量估计的非参数经验Bayes和复合决策方法

Nonparametric empirical Bayes and compound decision approaches to estimation of a high-dimensional vector of normal means

Lawrence D. Brown, Eitan Greenshtein

摘要:

我们考虑的经典问题,估计一个向量$\boldsμ=(μ_1,...,μ_n)$的基础上独立的意见$Y_i\sim N(μ_i,1)$,$i=1,...,n$。假设$μ_i$、$i=1,...,n$是来自完全未知的$G$的独立实现。我们建议一个容易计算的估计$\hat{\boldsμ}$,使其风险比$E(\hat{\boldsμ}-\boldsμ)^2$与贝叶斯过程接近1。并给出了相关的复合判决结果。我们的渐近是一个三角形阵列,也就是说,我们允许分布$G$依赖于$n$。因此,我们的理论渐近结果也有意义的情况下,矢量$\boldsμ$是稀疏的,零坐标的比例接近1。我们证明了我们的估计在模拟中的性能,强调稀疏设置。在“适度稀疏”的情况下,我们的程序执行得非常好相比,为稀疏设置定制的已知程序。它也能很好地适应非稀疏的情况。

英文摘要:

We consider the classical problem of estimating a vector $\boldsμ=(μ_1,...,μ_n)$ based on independent observations $Y_i\sim N(μ_i,1)$, $i=1,...,n$. Suppose $μ_i$, $i=1,...,n$ are independent realizations from a completely unknown $G$. We suggest an easily computed estimator $\hat{\boldsμ}$, such that the ratio of its risk $E(\hat{\boldsμ}-\boldsμ)^2$ with that of the Bayes procedure approaches 1. A related compound decision result is also obtained. Our asymptotics is of a triangular array; that is, we allow the distribution $G$ to depend on $n$. Thus, our theoretical asymptotic results are also meaningful in situations where the vector $\boldsμ$ is sparse and the proportion of zero coordinates approaches 1. We demonstrate the performance of our estimator in simulations, emphasizing sparse setups. In ``moderately-sparse'' situations, our procedure performs very well compared to known procedures tailored for sparse setups. It also adapts well to nonsparse situations.

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。

↑