Wright, Peter A. - In: Statistics & Probability Letters 47 (2000) 3, pp. 249-251
We derive an explicit form for the cumulative distribution function of both the Chan et al. (J. Quality Technol. 20 (1988) 162-175) estimator and the Boyles (J. Quality Technol. 23 (1991) 17-26) estimator of the process capability index Cpm when sampling from a normal distribution.
