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A Graphical Approach for Interpreting Out-of-Control Signals in Multivariate Control Charts
ISSN: 0148-7191, e-ISSN: 2688-3627
Published January 13, 2020 by SAE International in United States
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Dealing with several variables simultaneously is not a simple task for quality engineers because the interpretation of out-of-control signals involves the examination of the data from a multivariate perspective. In this paper, a graphical technique for interpreting out-of-control signals in multivariate control charts is proposed. This approach consists of a typical Hotelling’s chart with warning labels indicating:1) the univariate out-of-control points often masked by the T-squared statistic; 2) the plane of the biplot that should be investigated to identify the cause of the signal. The idea of using biplots as a complementary tool is to provide a broader view of the data without adding much complexity to the analysis. Finally, the benefits of this are shown through a case example of an automotive body assembly process.
CitationPargas Carmona, L., "A Graphical Approach for Interpreting Out-of-Control Signals in Multivariate Control Charts," SAE Technical Paper 2019-36-0068, 2020, https://doi.org/10.4271/2019-36-0068.
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