One-sided variable sampling interval EWMA control charts for monitoring the multivariate coefficient of variation in the presence of measurement errors

Online monitoring of the multivariate coefficient variation (MCV) can be interest in many real situations which dispersion a process is meant to remain constant with regard its position. To this aim, several control charts have been recently proposed literature. In paper, new one-sided adaptive monitor MCV are proposed. The chart applies variable sampling interval (VSI) strategy on an exponentially weighted moving average (EWMA) scheme, aiming at benefiting from known advantages both approaches. Formulas optimally determine parameters derived and presented. shown outperform competing under most circumstances. presence measurement errors considered understand their effects charts. An illustrative example also included.