“…For the adaptive approach in variable charts, it has been shown to give substantially faster detection of most process shifts than the traditional charts (see Bai and Lee, 2002;Costa, 1994Costa, , 1999Rahim, 2006, Costa andMagalhaes, 2007;Lina and Chou, 2005;Prabhu et al, 1994;Reynolds and Stoumbos, 2001;Yang and Chen, 2009;Yang and Rahim, 2005;Yang and Su, 2007;Yang et al, 2010;Wu et al, 2007;Zhang and Wu, 2006;Zimmer et al, 1998Zimmer et al, , 2000. For the traditional attributes charts, in the previous works, they are based on the conforming run length (CRL) to detect the out-of-control condition by checking the number of nonconforming unit or nonconformities in a sample (see Bourke, 1991Bourke, , 2001Kaminsky et al, 1992;Wu and Spedding, 2000;Wu et al, 2001a, b).…”