arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1709.04342stat.MEmath.STstat.TH
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基于似然比检验的模型选择置信集

Model Selection Confidence Sets by Likelihood Ratio Testing

Chao Zheng, Davide Ferrari, Yuhong Yang

摘要:

传统的模型选择活动旨在发现优于其他候选模型的单个模型。然而,在存在明显噪音的情况下,往往会发现多个模型同样能很好地解释相同的数据。为了解决这一模型选择模糊性问题,提出了基于似然比检验的模型选择置信集(MSCSs)的一般方法。MSCS被定义为在用户指定的置信水平下与真实模型在统计上不可区分的模型列表,其将置信区间的熟悉概念扩展到模型选择框架。当样本量和模型维数都增加时,我们的方法保证了真实模型的渐近正确覆盖概率。我们推导出的条件下,MSCS包含所有相关信息的真实模型结构。此外,我们提出了基于MSCS的自然统计,以一种原则性的方式来衡量变量的重要性,这种方式考虑了整个模型的不确定性。当可行模型空间较大时,采用自适应随机搜索算法对MSCS模型进行高概率采样。通过对合成数据和实际数据的数值实验,说明了MSCS方法。

英文摘要:

The traditional activity of model selection aims at discovering a single model superior to other candidate models. In the presence of pronounced noise, however, multiple models are often found to explain the same data equally well. To resolve this model selection ambiguity, we introduce the general approach of model selection confidence sets (MSCSs) based on likelihood ratio testing. A MSCS is defined as a list of models statistically indistinguishable from the true model at a user-specified level of confidence, which extends the familiar notion of confidence intervals to the model-selection framework. Our approach guarantees asymptotically correct coverage probability of the true model when both sample size and model dimension increase. We derive conditions under which the MSCS contains all the relevant information about the true model structure. In addition, we propose natural statistics based on the MSCS to measure importance of variables in a principled way that accounts for the overall model uncertainty. When the space of feasible models is large, MSCS is implemented by an adaptive stochastic search algorithm which samples MSCS models with high probability. The MSCS methodology is illustrated through numerical experiments on synthetic data and real data examples.

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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