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Publication Citation: Comparisons of Estimators of process standard deviation in constructing Shewhart control charts with unequal subgroup sizes

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Author(s): Nien F. Zhang; P Winkel;
Title: Comparisons of Estimators of process standard deviation in constructing Shewhart control charts with unequal subgroup sizes
Published: January 20, 2010
Abstract: The and control charts with unequal subgroup size have been discussed in the literature and used in practice. Several estimators of the process standard deviation based on sample standard deviations have been proposed in constructing the charts. We discuss the properties of these estimators and make comparisons using the criterion of minimum mean square error. The and control charts based on the recommended estimator of the process standard deviation is also discussed
Citation: Quality Engineering
Pages: 9 pp.
Keywords: Biased Estimator;Control limit;Linear combination;Minimum variance;Relative difference
Research Areas:
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