An EWMA control chart using two parametric ratio estimator

Abstract

The control chart is one of the important industrial tools used for monitoring the manufacturing process. The performance of control chart may enhance when some additional information about variable under study is available. In this article, a new two parametric ratio estimator is introduced to design the exponentially weighted moving average control chart. The proposed control chart is more efficient than the existing control chart in detecting small and moderate shifts in the process mean at Phase II. The application of proposed control chart in the industry is given with the aid of a real example.