h-Statistic
The h-statistic h_r is the unique symmetric unbiased estimator for a central moment of a distribution
| <h_r>=mu_r. |
(1)
|
In addition, the variance
| var(h_r)=<(h_r-mu_r)^2> |
(2)
|
is a minimum compared to all other unbiased estimators (Halmos 1946; Rose and Smith 2002, p. 254). The first few are given in terms of power sums by
h_1 =
(3)
h_2 = [画像:(nS_2-S_1^2)/((n-1)n)]
(4)
h_3 = [画像:(2S_1^3-3nS_1S_2+n^2S_3)/((n-2)(n-1)n)]
(5)
and in terms of sample central moments by
These can be given by HStatistic[r] and HStatisticToSampleCentral[r], respectively, in the Wolfram Language application package mathStatica.
See also
Central Moment, k-Statistic, PolyacheExplore with Wolfram|Alpha
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References
Dwyer, P. S. "Moments of Any Rational Integral Isobaric Sample Moment Function." Ann. Math. Stat. 8, 21-65, 1937.Halmos, P. R. "The Theory of Unbiased Estimation." Ann. Math. Stat. 17, 34-43, 1946.Rose, C. and Smith, M. D. "h-Statistics: Unbiased Estimators of Central Moments." §7.2B in Mathematical Statistics with Mathematica. New York: Springer-Verlag, pp. 253-256, 2002.Referenced on Wolfram|Alpha
h-StatisticCite this as:
Weisstein, Eric W. "h-Statistic." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/h-Statistic.html