Multivariate EWMA Control Charts for Monitoring Dispersion Matrix



Chang Duk-Joon;Lee Jae Man

  • 발행 : 2005.08.01


In this paper, we proposed multivariate EWMA control charts for both combine-accumulate and accumulate-combine approaches to monitor dispersion matrix of multiple quality variables. Numerical performance of the proposed charts are evaluated in terms of average run length(ARL). The performances show that small smoothing constants with accumulate-combine approach is preferred for detecting small shifts of the production process.


multivariate control chart;ARL;accumulate-combine approach


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