the applications of runs rules have significantly
improve the performance of the charts [6]. This however, is
not the case with the PEWMA chart. The application of a
simple 2
2 rule on the later is worse than the classical PEWMA
chart (cf. Tables I-VI). It is the least performing scheme in
terms of ARL, AEQL, PCI and ARARL, in detecting mean
changes in Poisson processes.