The modified double sampling coefficient of variation control chart

Rozi, Fachrur ORCID:, Pasaribu, Udjianna Sekteria, Mukhaiyar, Utriweni and Irianto, Dradjad (2023) The modified double sampling coefficient of variation control chart. Journal of Mathematical and Fundamental Sciences, 55 (1). pp. 56-76. ISSN 2337-5760

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The concept of monitoring the coefficient of variation has gained significant interest in quality control, particularly in situations where the mean and standard deviation of a process are not constant. This study modified the procedure of the previous double sampling chart for monitoring the coefficient of variation, developed by Ng et 2018. Instead of using only information from the second sample, here, information from both samples is used. The probability properties of the out-of-control signal and the run length of this chart are presented. To evaluate the chart’s performance, the optimal design and a comparison with the previous double sampling control chart using average run-length criteria are described. It was found that the modified double sampling chart has better performance and is more efficient compared to the previous chart, especially when the total sample size is smaller. As a study case, the application of this chart is illustrated using real data from a molding process. This confirmed that the modified double sampling chart improved performance in detecting out-of-control signals. Thus, the modified chart is recommended to be applied in industry.

Item Type: Journal Article
Keywords: coefficient of variation; control chart; double sampling; run length; molding process.
Subjects: 01 MATHEMATICAL SCIENCES > 0104 Statistics > 010405 Statistical Theory
09 ENGINEERING > 0910 Manufacturing Engineering > 091008 Manufacturing Safety and Quality
01 MATHEMATICAL SCIENCES > 0104 Statistics
Divisions: Faculty of Mathematics and Sciences > Department of Mathematics
Depositing User: Fachrur Rozi
Date Deposited: 23 Oct 2023 13:25


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