中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
The asymptotic variance-covariance matrix, Baarda test and the reliability of L-1-norm estimates

文献类型:期刊论文

作者Junhuan, P
刊名JOURNAL OF GEODESY
出版日期2005-05-01
卷号78期号:11-12页码:668-682
关键词L-1-norm estimate modified L-1-norm estimate Bahadur-type linear representation asymptotic variance covariance matrix Baarda test statistic reliability outliers/gross errors leverage points robust estimation
英文摘要This paper derives the complete Bahadur-type linear representation of the basic vector including the residual vector and the adjusted vector of the observations for the L-1-norm estimation. The asymptotic variance-covariance matrix of the basic vector is obtained accordingly. The L-1-Baarda test statistic is successfully obtained from the residual and its variance. The reliability, understood as the ability to detect as well as resist outliers, of the L-1 -norm estimate is discussed for the L-1-Baarda test statistic, as compared with the reliability of the L-2-norm estimate; it is less affected by the variation of the redundancy component. According to the relationship between residuals and true errors for the L-1 norm estimate, the outlier is almost completely projected onto the corresponding residual. This is why the L-1-Baarda test seems to locate outliers more correctly. For the L-2 -norm estimates, the outlier is partly projected onto the corresponding residual at the proportion of the corresponding redundancy component, which may easily result in an error of the third kind - the mis-location of the outlier through the L-2-Baarda test. Besides, the robustness of the L-1-norm estimate is no longer guaranteed if there exist leverage points in observations. This paper suggests the modified L-1-norm estimate for robust estimation of leverage points, and derives its Bahadur-type representation and the corresponding variance-covariance matrix. In numerical examples, the L-1-norm estimate and modified L-1-norm estimate are compared with the L-2-norm estimate, Biber-estimate, Koch's method and the least median of squares method. The result shows that the L-1-norm estimation can better identify small outliers, and that the modified L-1-norm estimate is valid for robust estimation in the presence of leverage points.
WOS标题词Science & Technology ; Physical Sciences ; Technology
类目[WOS]Geochemistry & Geophysics ; Remote Sensing
研究领域[WOS]Geochemistry & Geophysics ; Remote Sensing
关键词[WOS]OUTLIER DETECTION ; LINEAR-MODELS ; REGRESSION
收录类别SCI
语种英语
WOS记录号WOS:000229856700004
源URL[http://119.78.226.72/handle/331011/19372]  
专题上海天文台_天文地球动力学研究中心
作者单位1.Chongqing Univ, Sch Civil Engn, Chongqing 400044, Peoples R China
2.CAS, Shanghai Astron Observ, Shanghai 200030, Peoples R China
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GB/T 7714
Junhuan, P. The asymptotic variance-covariance matrix, Baarda test and the reliability of L-1-norm estimates[J]. JOURNAL OF GEODESY,2005,78(11-12):668-682.
APA Junhuan, P.(2005).The asymptotic variance-covariance matrix, Baarda test and the reliability of L-1-norm estimates.JOURNAL OF GEODESY,78(11-12),668-682.
MLA Junhuan, P."The asymptotic variance-covariance matrix, Baarda test and the reliability of L-1-norm estimates".JOURNAL OF GEODESY 78.11-12(2005):668-682.

入库方式: OAI收割

来源:上海天文台

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