... , and the shift in the mean is δ σ Y , with δ ≥ 0 . As the observations are independents with variance σ 2 , the variance of Z t is Average run length EWMA control chart Autoregressive processes Skewed distributions Simulation study Manufacturing processes...

... * , respectively, and Chan and Cui (2003) and Riaz et al. (2016) calculated these factors on the basis of six skewed distributions which are considered to be representatives of skewed processes. These factors are used as substitutes of unbiased estimators when true control limit parameters are unknown...