arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1502.06895math.STcs.LGstat.MLstat.TH
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关于高维变量筛选的一致性理论

On the consistency theory of high dimensional variable screening

Xiangyu Wang, Chenlei Leng, David B. Dunson

摘要:

变量筛选是一种快速降维技术,用于辅助高维特征选择。作为一种预选方法,它选择一个中等大小的候选变量子集,通过特征选择进一步细化,以产生最终的模型。变量筛选的性能取决于计算效率和在不丢弃重要变量的情况下显著减少变量数量的能力。当数据维度$p$显著大于样本量$n$时,变量筛选变得至关重要,因为1)需要更快的特征选择算法; 2)保证选择一致性的条件可能无法保持。研究了一类线性筛选方法,建立了这类方法的相容性理论。特别地,我们证明了限制对角占优(RDD)条件是强屏蔽一致性的充要条件。作为具体的例子,我们表明两个筛选方法$SIS$和$HOLP$都是强筛选一致的(受到额外的约束),以大概率,如果$n > O((ρs + σ/τ)^2\log p)$在随机设计。此外,我们与RDD条件的不可表示的条件,并强调$SIS$的局限性。

英文摘要:

Variable screening is a fast dimension reduction technique for assisting high dimensional feature selection. As a preselection method, it selects a moderate size subset of candidate variables for further refining via feature selection to produce the final model. The performance of variable screening depends on both computational efficiency and the ability to dramatically reduce the number of variables without discarding the important ones. When the data dimension $p$ is substantially larger than the sample size $n$, variable screening becomes crucial as 1) Faster feature selection algorithms are needed; 2) Conditions guaranteeing selection consistency might fail to hold. This article studies a class of linear screening methods and establishes consistency theory for this special class. In particular, we prove the restricted diagonally dominant (RDD) condition is a necessary and sufficient condition for strong screening consistency. As concrete examples, we show two screening methods $SIS$ and $HOLP$ are both strong screening consistent (subject to additional constraints) with large probability if $n > O((ρs + σ/τ)^2\log p)$ under random designs. In addition, we relate the RDD condition to the irrepresentable condition, and highlight limitations of $SIS$.

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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