A generalized statistical control chart for over- or under-dispersed data

作者：Sellers Kimberly F^*

来源：Quality and Reliability Engineering International, 2012, 28(1): 59-65.

DOI：10.1002/qre.1215

• attribute control chart
• Conway-Maxwell-Poisson distribution
• count data
• Poisson distribution
• Shewhart control chart

The Poisson distribution is a popular distribution used to describe count information, from which control charts involving count data have been established. Several works recognize the need for a generalized control chart to allow for data over-dispersion; however, analogous arguments can also be made to account for potential under-dispersion. The ConwayMaxwellPoisson (COM-Poisson) distribution is a general count distribution that relaxes the equi-dispersion assumption of the Poisson distribution, and in fact encompasses the special cases of the Poisson, geometric, and Bernoulli distributions. Accordingly, a flexible control chart is developed that encompasses the classical Shewart charts based on the Poisson, Bernoulli (or binomial), and geometric (or negative binomial) distributions.

• 出版日期2012-2