A new control chart for exponential distributed life using EWMA

In this paper, we present a new control chart for exponentially distributed quality characteristics using variable transformation and exponentially weighted moving average (EWMA). The in-control and out-of-control average run lengths (ARLs) are derived using the normal approximation. The parameters of the proposed control chart are determined by considering the target in-control ARL. The efficiency of the proposed control chart is discussed in terms of ARLs over the existing control chart without using EWMA. The application of the proposed control chart is discussed with the help of a real example.

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