Outlier treatment in data merging

被引:1435
作者
Blessing, RH
机构
[1] Hauptman-Woodward Institute, Buffalo, NY 14203-1196
关键词
D O I
10.1107/S0021889896014628
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Experience with a variety of diffraction data-reduction problems has led to several strategies for dealing with mismeasured outliers in multiply measured data sets. Key features of the schemes employed currently include outlier identification based on the values y(median) = median(\F-i\(2)), sigma(median) = median[sigma(\F-i\(2))], and \Delta\median = median(\Delta(i)\) = median[\\F-i\(2)-median (\F-i\(2))\] in samples with i=1,2,...,n and n greater than or equal to 2 measurements; and robust/resistant averaging weights based on values of \z(i)\=\Delta(i)\/ max{sigma(median), \Delta\(median)[n/(n-1)](1/2). For outlier discrimination or down-weighting, sample median values have the advantage of being much less outlier-based than sample mean values would be.
引用
收藏
页码:421 / 426
页数:6
相关论文
共 12 条
  • [1] Blessing R. H., 1989, Journal of Applied Crystallography, V22, P396, DOI 10.1107/S0021889889001639
  • [2] Blessing R. H., 1987, Crystallogr. Rev, V1, P3, DOI [10.1080/08893118708081678, DOI 10.1080/08893118708081678]
  • [3] DATA AVERAGING WITH NORMAL DOWN-WEIGHTING OF OUTLIERS
    BLESSING, RH
    LANGS, DA
    [J]. JOURNAL OF APPLIED CRYSTALLOGRAPHY, 1987, 20 : 427 - 428
  • [4] AN EMPIRICAL CORRECTION FOR ABSORPTION ANISOTROPY
    BLESSING, RH
    [J]. ACTA CRYSTALLOGRAPHICA SECTION A, 1995, 51 : 33 - 38
  • [5] TREATMENT OF NEGATIVE INTENSITY OBSERVATIONS
    FRENCH, S
    WILSON, K
    [J]. ACTA CRYSTALLOGRAPHICA SECTION A, 1978, 34 (JUL): : 517 - 525
  • [6] STRUCTURE OF A SILICON CARBIDE POLYTYPE 24R
    HAMILTON, WC
    ROLLETT, JS
    SPARKS, RA
    [J]. ACTA CRYSTALLOGRAPHICA, 1965, 18 : 129 - &
  • [7] PRESS WH, 1986, NUMERICAL RECIPES AR, P229
  • [8] PRINCE E, 1982, MATH TECHNIQUES CRYS, P77
  • [9] STATISTICAL DESCRIPTORS IN CRYSTALLOGRAPHY REPORT OF THE INTERNATIONAL UNION OF CRYSTALLOGRAPHY SUBCOMMITTEE ON STATISTICAL DESCRIPTORS
    SCHWARZENBACH, D
    ABRAHAMS, SC
    FLACK, HD
    GONSCHOREK, W
    HAHN, T
    HUML, K
    MARSH, RE
    PRINCE, E
    ROBERTSON, BE
    ROLLETT, JS
    WILSON, AJC
    [J]. ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, 1989, 45 : 63 - 75
  • [10] STATISTICAL DESCRIPTORS IN CRYSTALLOGRAPHY .2. REPORT OF A WORKING GROUP ON EXPRESSION OF UNCERTAINTY IN MEASUREMENT
    SCHWARZENBACH, D
    ABRAHAMS, SC
    FLACK, HD
    PRINCE, E
    WILSON, AJC
    [J]. ACTA CRYSTALLOGRAPHICA SECTION A, 1995, 51 : 565 - 569