StatPub Date : 2025-09-01Epub Date: 2025-08-22DOI: 10.1002/sta4.70094
Tianzhou Ma, Fan Yang, Hongjie Ke, Zhao Ren
{"title":"Robust Distance Correlation for Variable Screening.","authors":"Tianzhou Ma, Fan Yang, Hongjie Ke, Zhao Ren","doi":"10.1002/sta4.70094","DOIUrl":"10.1002/sta4.70094","url":null,"abstract":"<p><p>In modern statistical applications, identifying critical features in high-dimensional data is essential for scientific discoveries. Traditional best subset selection methods face computational challenges, while regularization approaches such as Lasso, SCAD and their variants often exhibit poor performance with ultrahigh-dimensional data. Sure screening methods, widely used for dimensionality reduction, have been developed as popular alternatives, but few target heavy-tailed characteristics in modern big data. This paper introduces a new sure screening method, based on robust distance correlation ('RDC'), designed for heavy-tailed data. The proposed method inherits the benefits of the original model-free distance correlation-based screening while robustly estimating distance correlation in the presence of heavy-tailed data. We further develop an FDR control procedure by incorporating the Reflection via Data Splitting (REDS) method. Extensive simulations demonstrate the method's advantage over existing screening procedures under different scenarios of heavy-tailedness. Its application to high-dimensional heavy-tailed RNA-seq data from The Cancer Genome Atlas (TCGA) pancreatic cancer cohort showcases superior performance in identifying biologically meaningful genes predictive of MAPK1 protein expression critical to pancreatic cancer.</p>","PeriodicalId":521200,"journal":{"name":"Stat","volume":"14 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13450041/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148698749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StatPub Date : 2025-03-01Epub Date: 2025-02-27DOI: 10.1002/sta4.70046
Salil Koner, Sheng Luo
{"title":"Power and sample size calculation of two-sample projection-based testing for sparsely observed functional data.","authors":"Salil Koner, Sheng Luo","doi":"10.1002/sta4.70046","DOIUrl":"10.1002/sta4.70046","url":null,"abstract":"<p><p>Projection-based testing for mean trajectory differences in two groups of irregularly and sparsely observed functional data has garnered significant attention in the literature because it accommodates a wide spectrum of group differences and (non-stationary) covariance structures. This article presents the derivation of the theoretical power function and the introduction of a comprehensive power and sample size (PASS) calculation toolkit tailored to the projection-based testing method developed by Wang<sup>1</sup>. Our approach accommodates a wide spectrum of group difference scenarios and a broad class of covariance structures governing the underlying processes. Through extensive numerical simulation, we demonstrate the robustness of this testing method by showcasing that its statistical power remains nearly unaffected even when a certain percentage of observations are missing, rendering it \"missing-immune\". Furthermore, we illustrate the practical utility of this test through analysis of two randomized controlled trials of Parkinson's disease. To facilitate implementation, we provide a user-friendly R package fPASS, complete with a detailed vignette to guide users through its practical application. We anticipate that this article will significantly enhance the usability of this potent statistical tool across a range of biological applications, with a particular focus on its relevance in the design of clinical trials.</p>","PeriodicalId":521200,"journal":{"name":"Stat","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12799244/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145971665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}