PROPAGATION OF OUTLIERS IN MULTIVARIATE DATA

• 成果类型: Article
• 署名作者: Alqallaf, Fatemah; Van Aelst, Stefan; Yohai, Victor J.; Zamar, Ruben H.
• 署名单位: Kuwait University; Ghent University; University of Buenos Aires; University of British Columbia
• 刊物名称: ANNALS OF STATISTICS
• ISSN/ISSBN: 0090-5364
• DOI: 10.1214/07-AOS588
• 发表日期: 2009
• 页码: 311-331
• 关键词: m-estimators; location; scatter; covariance; regression; matrices; BIAS

摘要

We investigate the performance of robust estimates of multivariate location under nonstandard data contamination models such as componentwise outliers (i.e., contamination in each variable is independent from the other variables). This model brings up a possible new source of statistical error that we call propagation of outliers. This source of error is Unusual in the sense that it is generated by the data processing itself and takes place after the data has been collected. We define and derive the influence function of robust multivariate location estimates under flexible contamination models and use it to investigate the effect of propagation of outliers. Furthermore, we show that standard high-breakdown affine equivariant estimators propagate outliers and therefore show poor breakdown behavior under componentwise contamination when the dimension d is high.