H. Shore, A NEW APPROACH TO ANALYZING NONNORMAL QUALITY DATA WITH APPLICATION TO PROCESS CAPABILITY ANALYSIS, International Journal of Production Research, 36(7), 1998, pp. 1917-1933
Citations number
37
Categorie Soggetti
Engineering,"Operatione Research & Management Science
A new approach to analysing non-normal quality data is proposed and de
monstrated for process capability analysis. The new approach uses a ne
w family of distributions and its allied fitting procedures to approxi
mate an unknown source distribution, and then incorporates the fitted
distribution in the relevant quality procedure. Since the new fitting
routines require only low degree sample moments (second degree at most
), the fitted distribution is associated with appreciably smaller mean
-squared-errors (MSEs) relative to those of alternative methods (3- or
4-moment routines). New first- second- and third-generation process c
apability indices (PCIs) for non-normal populations, analogous to curr
ent PCIs developed for Pearsonian populations, are developed and numer
ically demonstrated. Sample estimators for the new PCIs are compared i
n terms of MSEs, via Monte Carlo simulation, to available four-moment
estimators for Pearsonian populations. The new PCIs consistently yield
smaller MSEs.