On the Steady-State Performance of the Poisson Double GWMA Control Chart

This article presents a control chart called "Poisson double GWMA" (PDGWMA) chart for monitoring Poisson-distributed processes. Using simulation, the steady-state average run length (SSARL) of PDGWMA chart is evaluated and compared with those of other control charts including Poisson EWMA, Poisson GWMA and Poisson double EWMA (PDEWMA). It is shown that this chart is always more sensitive than other control charts in detecting an out-of-control signal. The PDGWMA chart is a generalized model for which the PDEWMA chart is a special case and also is an effective control chart in situations where the quality deterioration (upward shift) and the quality improvement (downward shift) can be detected agilely, which is important to a modern advanced system.