This paper develops a stacked ensemble EWMA (SE-EWMA) chart for Phase II monitoring of process location. The aim is to give practitioners one calibrated alarm rule that uses both mean based and median based evidence, rather than forcing a prior choice between efficiency under light tailed behavior and stability under heavy tailed or skewed behavior. The two EWMA paths are converted into exceedance evidence scores and combined through a logistic stacking rule. A single threshold is calibrated by Monte Carlo simulation to attain the desired in control average run length while accounting for dependence between the two paths. The simulation study covers shifts, linear drifts, and quadratic...

| Arabian Journal for Science and Engineering Navigating Process Drift: The Power of CUSUM in Monitoring Air Quality Processes and Maintenance Operations | Arabian Journal for Science and Engineering