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

Published

Author(s)

Nien F. Zhang, P Winkel

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

Keywords

Biased Estimator, Control limit, Linear combination, Minimum variance, Relative difference

Citation

Zhang, N. and Winkel, P. (2010), Comparisons of Estimators of process standard deviation in constructing Shewhart control charts with unequal subgroup sizes, Quality Engineering, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=51243 (Accessed May 24, 2024)

Issues

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Created January 20, 2010, Updated January 27, 2020