Summary
LetX be ak-dimensional random vector with mean vectorμ and non-singular covariance matrix Σ. We show that among all pairs (a, Δ),a ∈ IRk, Δ ∈ IRk×k positive definite and symmetric andE(X−a)′ Δ−1(X−a)=k, (μ, Σ) is the unique pair which minimizes det Δ. This motivates certain robust estimators of location and scale.
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References
Davies PL (1986) Asymptotic behavior ofS-estimates of multivariate location parameters and dispersion matrices. Preprint, Essen
Hampel FR, Ronchetti EM, Rousseeuw PJ, Stahel WA (1986) Robust statistics: the approach based on influence functions. Wiley, New York
Rousseeuw PJ (1985) Multivariate estimation with high breakdown point. In: Grossmann W, Pflug G, Vincze I, Wertz W (eds) Mathematical statistics and applications. Reidel Publishing Company, Dordrecht, pp 283–297
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Research supported by the Nuffield Foundation.
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Grübel, R. A minimal characterization of the covariance matrix. Metrika 35, 49–52 (1988). https://doi.org/10.1007/BF02613285
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DOI: https://doi.org/10.1007/BF02613285