Generalization of time‐varying fast initial response for exponentially weighted moving average control charts

Abstract

AbstractFor monitoring processes, exponentially weighted moving average (EWMA) control charts have been found to be very powerful and reliable tools. Meanwhile, some processes require great attention at the startup to ascertain that the processes are free from any disturbances. In this article, we propose a generalized time‐varying fast initial response for EWMA control charts. This chart is a special case of the previously proposed time‐varying EWMA control chart. The proposed scheme is highly sensitive in detecting small shifts in a given process, particularly at the process startup. The proposed chart is compared with its counterparts using the zero state average run length. We also show an application of the proposed EWMA chart to a real‐life situation.