Department of Statistics, University of Nigeria, Nsukka, Enugu State, Nigeria.


Department of Statistics, University of Nigeria, Nsukka, Enugu State, Nigeria.


Department of Statistics, University of Nigeria, Nsukka, Enugu State, Nigeria.

*Author to whom correspondence should be addressed.


Multivariate statistical process control charts are used for process monitoring and control of two or more variables simultaneously for quality and quality improvement. A popular multivariate control chart is used to monitor the mean vector of the process. A usual problem in the multivariate control chart is the identification and interpretation of variable(s) for an out-of-control signal that occurred in the chart. This has brought many developed techniques from many researchers to aid in finding the responsible variable(s) that caused the out-of-control signal in the chart. This work is aimed at a comparative study of some developed techniques for identifying and interpreting an out-of-control signal, in the multivariate control chart when applied on the cable production process. The techniques are Mason-Tracy-Young, Donganaksoy-Faltin-Tucker, Univariate -chart using Bonferroni control limits by Alt and Principal component analysis by Jackson. A performance criterion, the power of the test was used to ascertain the most satisfactory technique that explained the out-of-control signal that occurred in -chart. From the results and discussions, Mason Tracy-Young and Doganaksoy-Faltin-Tucker techniques are the most satisfactory for identifying and interpreting an out-of-control signal in the multivariate control chart.

Keywords: Multivariate statistical process control chart, multivariate control chart interpretation, power of a test, cable products

How to Cite

UDOM, A. U., EZEANI, O. M., & ODOH, N. P. (2022). ON TECHNIQUES FOR IDENTIFICATION OF OUT-OF-CONTROL VARIABLE(S) IN MULTIVARIATE T2 CONTROL CHART ON CABLE PRODUCTION. Asian Journal of Mathematics and Computer Research, 29(2), 7–22. https://doi.org/10.56557/ajomcor/2022/v29i27874


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