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arXiv 0712.0904math.STstat.TH
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正态均值问题中贝叶斯估计的最优性

On optimality of Bayesian testimation in the normal means problem

Felix Abramovich, Vadim Grinshtein, Marianna Pensky

摘要:

我们考虑一个问题,恢复一个高维向量$μ$观察白噪声,其中未知向量$μ$被假定为稀疏。本文的目的是发展贝叶斯形式主义,从而产生一个家庭的$l_0$型的处罚。罚分与$μ$的非零条目数上的先验分布$π_n(\cdot)$的各种选择相关联,因此易于解释。由此产生的贝叶斯估计导致一个一般的阈值规则,它容纳了许多已知的阈值和模型选择程序作为特定的情况下,对应于特定的选择$π_n(\cdot)$。此外,他们实现了最优性,在一个相当一般的设置在非常温和的条件下的先验。我们还指定类的先验$π_n(\cdot)$,由此产生的估计是自适应最佳的(在极大极小意义上)的稀疏序列的范围很广,并考虑这样的先验的几个例子。

英文摘要:

We consider a problem of recovering a high-dimensional vector $μ$ observed in white noise, where the unknown vector $μ$ is assumed to be sparse. The objective of the paper is to develop a Bayesian formalism which gives rise to a family of $l_0$-type penalties. The penalties are associated with various choices of the prior distributions $π_n(\cdot)$ on the number of nonzero entries of $μ$ and, hence, are easy to interpret. The resulting Bayesian estimators lead to a general thresholding rule which accommodates many of the known thresholding and model selection procedures as particular cases corresponding to specific choices of $π_n(\cdot)$. Furthermore, they achieve optimality in a rather general setting under very mild conditions on the prior. We also specify the class of priors $π_n(\cdot)$ for which the resulting estimator is adaptively optimal (in the minimax sense) for a wide range of sparse sequences and consider several examples of such priors.

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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