TY - JOUR
T1 - A multivariate exponentially weighted moving average control chart for monitoring process variability
AU - Yeh, Arthur B.
AU - Lin, Dennis K.J.
AU - Zhou, Honghong
AU - Venkataramani, Chandramouliswaran
PY - 2003/6
Y1 - 2003/6
N2 - This paper introduces a new multivariate exponentially weighted moving average (EWMA) control chart. The proposed control chart, called an EWMA V-chart, is designed to detect small changes in the variability of correlated multivariate quality characteristics. Through examples and simulations, it is demonstrated that the EWMA V-chart is superior to the S-chart in detecting small changes in process variability. Furthermore, a counterpart of the EWMA V-chart for monitoring process mean, called the EWMA M-chart is proposed. In detecting small changes in process variability, the combination of EWMA M-chart and EWMA V-chart is a better alternative to the combination of MEWMA control chart (Lowry et al., 1992) and S-chart. Furthermore, the EWMA M-chart and V-chart can be plotted in one single figure. As for monitoring both process mean and process variability, the combined MEWMA and EWMA V-charts provide the best control procedure.
AB - This paper introduces a new multivariate exponentially weighted moving average (EWMA) control chart. The proposed control chart, called an EWMA V-chart, is designed to detect small changes in the variability of correlated multivariate quality characteristics. Through examples and simulations, it is demonstrated that the EWMA V-chart is superior to the S-chart in detecting small changes in process variability. Furthermore, a counterpart of the EWMA V-chart for monitoring process mean, called the EWMA M-chart is proposed. In detecting small changes in process variability, the combination of EWMA M-chart and EWMA V-chart is a better alternative to the combination of MEWMA control chart (Lowry et al., 1992) and S-chart. Furthermore, the EWMA M-chart and V-chart can be plotted in one single figure. As for monitoring both process mean and process variability, the combined MEWMA and EWMA V-charts provide the best control procedure.
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U2 - 10.1080/0266476032000053655
DO - 10.1080/0266476032000053655
M3 - Article
AN - SCOPUS:0037409837
SN - 0266-4763
VL - 30
SP - 507
EP - 536
JO - Journal of Applied Statistics
JF - Journal of Applied Statistics
IS - 5
ER -