A new nonparametric composite exponentially weighted moving average sign control chart

Abstract

This study proposed a dual ExponentiallyWeighted Moving Average (EWMA) statistics based nonparametric sign control chart to monitor the process deviation from the targeted value. The performance of the proposed chart is compared with the existing nonparametric version of the EWMA sign and Cumulative Sum (CUSUM) mean control charts by using out-of-control average run length for various shifts in the process. The simulation study showed the superiority of the suggested chart over the existing counterparts. A real dataset is also considered for the application of the proposed chart.