Honest confidence sets for high-dimensional regression by projection and shrinkage

التفاصيل البيبلوغرافية
العنوان: Honest confidence sets for high-dimensional regression by projection and shrinkage
المؤلفون: Zhou, Kun, Li, Ker-Chau, Zhou, Qing
المصدر: Journal of the American Statistical Association, 2021
سنة النشر: 2019
المجموعة: Mathematics
Statistics
مصطلحات موضوعية: Statistics - Methodology, Mathematics - Statistics Theory
الوصف: The issue of honesty in constructing confidence sets arises in nonparametric regression. While optimal rate in nonparametric estimation can be achieved and utilized to construct sharp confidence sets, severe degradation of confidence level often happens after estimating the degree of smoothness. Similarly, for high-dimensional regression, oracle inequalities for sparse estimators could be utilized to construct sharp confidence sets. Yet the degree of sparsity itself is unknown and needs to be estimated, causing the honesty problem. To resolve this issue, we develop a novel method to construct honest confidence sets for sparse high-dimensional linear regression. The key idea in our construction is to separate signals into a strong and a weak group, and then construct confidence sets for each group separately. This is achieved by a projection and shrinkage approach, the latter implemented via Stein estimation and the associated Stein unbiased risk estimate. Our confidence set is honest over the full parameter space without any sparsity constraints, while its diameter adapts to the optimal rate of $n^{-1/4}$ when the true parameter is indeed sparse. Through extensive numerical comparisons, we demonstrate that our method outperforms other competitors with big margins for finite samples, including oracle methods built upon the true sparsity of the underlying model.
Comment: 36 pages, 7 figures
نوع الوثيقة: Working Paper
DOI: 10.1080/01621459.2021.1938581
الوصول الحر: http://arxiv.org/abs/1902.00535Test
رقم الانضمام: edsarx.1902.00535
قاعدة البيانات: arXiv