Abstract
A control chart for attribute data, called p-Rp chart, was proposed by Y. Akao, which enables us to control substantial variations both within and between subgroups. This paper deals with is operating characteristics based on a beta-binomial model which describes the variations within a subgroup. As the result, the power of the p-Rp chart increases with the spot sample size, the number of samples and/or the percent defectives. Besides, the variaton between subgroups and the increase of the variation within a subgroup can be detected by the p chart and the Rp chart respectively. These imply that the p-Rp chart plays an important role on behalf of the conventional p or pn chart from the subgrouping viewpoint. In other words, the p-Rp chart corresponds to an x-R chart as a control chart for attribute data.
