Decreasing the effect of measurement errors on detecting and diagnosing performance of MAX-EWMAMS control chart in Phase II

In recent years, the quality practitioners have concentrated on exploring the effect of measurement errors on the performance of control charts. To the best of our knowledge, the effect of measurement errors on simultaneous monitoring of the process mean and the process variability is neglected in the literature. In this paper, the effect of measurement errors on detecting and diagnosing performance of one of the most common simultaneous monitoring approaches in the literature is investigated. Two approaches namely multiple measurement approach as well as increasing sample size are suggested for compensating for the effect of measurement errors. The results of simulation study show that the measurement errors can adversely affect the detecting performance of maximum exponentially weighted moving average and mean squared deviation (MAX-EWMAMS) control chart while the effect of measurement errors on diagnosing performance of this control chart is negligible. The results also represent that both tasking multiple measurement on each sample point and increasing sample size can adequately compensate for the measurement errors effect.