A new hybrid exponentially weighted moving average control chart : A new hybrid exponentially weighted moving average control chart using mixture ratio estimator of mean

We have proposed a New Hybrid Exponentially Weighted Moving Average HEWMA control chart. The proposed control chart is based on a mixture ratio estimator of the mean using a single auxiliary variable and a single auxiliary attribute (Moeen et al., 2012). We call it as Z- HEWMA control chart. The proposed control chart performance is evaluated using out-of-control-Average Run Length (ARL1). The control limits of the proposed chart is based on the estimator, its mean square errors. A simulated data is used to compare the proposed Z-HEWMA, traditional/simple EWMA chart and CUSUM control chart. From this study, the fact is revealed that Z-HEWMA control chart shows more efficient results as compared to traditional/simple EWMA and CUSUM control charts. The Z-HEWMA chart can be used for efficient monitoring of the production process in manufacturing industries where auxiliary information about a numerical variable and an attribute is available.