Performance of maximum EWMA control chart in the presence of measurement error using auxiliary information

Abstract

EWMA and Max-EWMA charts are considered efficient for individual as well as joint monitoring of mean and variance shifts in the production process. However, measurement error is affecting the efficiency of these charts. In this study we propose a maximum exponentially weighted moving average with measurement error using auxiliary information control chart and name it Max-EWMAMEAI control chart. The efficiency of this chart is highlighted and the effect of measurement error is shown by the values ofARLsandSDRLscalculated through simulations using linear covariate model. The case of linearly increasing variance is examined and multiple measurements technique has been applied to reduce the error effect. A real life example is also included to support the simulation results.