“…They showed that the -GWMA scheme performs better than the -EWMA scheme in monitoring small shifts in the process mean. Thereafter, a number of researchers investigated the performance of parametric GWMA schemes, to count a few, Sheu and Yang (2006), Sheu and Hsieh (2009), Tai and Lin (2009), Teh et al (2012), Aslam et al (2017), Chakraborty et al (2017), etc. SPM schemes have been applied to a variety of fields, including engineering, production, manufacturing, finance, food industry, chemistry and biochemistry, see Simoglou et al (1997), Black et al (2011), Bag et al (2012), Lim et al (2017), etc.…”