A review of dispersion control charts for multivariate individual observations. Issue Volume 33:Issues 1(2021) (2nd January 2021)

• Record Type: Journal Article
• Authors: Ajadi, Jimoh Olawale; Wang, Zezhong; Zwetsloot, Inez Maria
• Is Part Of: Quality engineering. Volume 33:Issues 1(2021)
• Page Start: 60
• Page End: 75
• Publication Date: 2021-01-02
• Subjects: CUSUM -- EWMA -- high-dimensional -- individual observations -- multivariate dispersion control chart -- non-parametric -- Shewhart; Quality control -- Periodicals; Production management -- Quality control -- Periodicals; 658.5
• DOI: 10.1080/08982112.2020.1755438
• Languages: English
• ISSNs: 0898-2112

Abstract

Abstract: A multivariate control chart is designed to monitor process parameters of multiple correlated quality characteristics. Often data on multivariate processes are collected as individual observations, i.e., as vectors one at a time. Various control charts have been proposed in the literature to monitor the covariance matrix of a process when individual observations are collected. In this study, we review the literature on control charts based on individual observations from multivariate continuous processes, where we find 30 relevant articles from the period 1987–2019. We group the articles into five categories. We observe that less research has been done on CUSUM, high-dimensional and non-parametric type control charts for monitoring the process covariance matrix. We describe each proposed method, state their advantages, and limitations. Finally, we give suggestions for future research.