Khoo, Michael B. C. and Atta, Abdu M. A. (2008) An EWMA control chart for monitoring the mean of skewed populations using weighted variance. In: IEEE International Conference on Industrial Engineering and Engineering Management 2008 (IEEM 2008), 8-11 Dec. 2008, Singapore.

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Abstract

This paper discusses the use of weighted variance (WV) in setting up the limits of the exponentially weighted moving average (EWMA) chart for the monitoring of the mean of a process from a skewed population. This chart, called the WV-EWMA chart hereafter, reduces to the standard EWMA chart when the underlying distribution is symmetric.The Type-I and Type-II errors of the WV-EWMA chart are compared with that of the existing charts for skewed populations. Simulation results show that the new method gives a considerable improvement over the existing methods when the underlying distribution is skewed.

Item Type:	Conference or Workshop Item (Paper)
Additional Information:	ISBN:978-1-4244-2630-0/08
Uncontrolled Keywords:	EWMA chart, X chart, skewed populations, Type-I error, Type-If error, weighted variance, weighted standard deviation, skewness correction
Subjects:	Q Science > QA Mathematics
Divisions:	College of Arts and Sciences
Depositing User:	Dr. Abdu Mohammed Ali Atta
Date Deposited:	09 Jul 2015 04:34
Last Modified:	09 Jul 2015 04:34
URI:	https://repo.uum.edu.my/id/eprint/14767

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