Robustness of variograms and conditioning of kriging matrices

  • Phil Diamond
  • Margaret Armstrong


Current ideas of robustness in geostatistics concentrate upon estimation of the experimental variogram. However, predictive algorithms can be very sensitive to small perturbations in data or in the variogram model as well. To quantify this notion of robustness, nearness of variogram models is defined. Closeness of two variogram models is reflected in the sensitivity of their corresponding kriging estimators. The condition number of kriging matrices is shown to play a central role. Various examples are given. The ideas are used to analyze more complex universal kriging systems.

Key words

variogram robustness kriging conditioning number 


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Copyright information

© Plenum Publishing Corporation 1984

Authors and Affiliations

  • Phil Diamond
    • 1
  • Margaret Armstrong
    • 2
  1. 1.Department of MathematicsUniversity of QueenslandSt. LuciaAustralia
  2. 2.Centre de Géostatistique et de Morphologie MathématiqueÉcole des Mines de ParisFontainebleauFrance

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