Estimating Process Capability Indices Using Univariate g and h Distribution

Process capability of a process is defined as inherent variability of a process which is running under chance cause of variation only. Process capability index is measuring the ability of a process to meet the product specification limit. Generally process capability is measured by 6 assuming that the product characteristic follows Normal distribution. In many practical situations the product characteristics do not follow normal distribution. In this paper, we describe an approach of estimating process capability assuming generalised g and h distribution proposed by Tukey.