Abstract
This paper presents a statistical analysis control chart for nonconforming units in quality control. In many situations the Shewhart control charts for nonconforming units may not be suitable or cannot be used. For many processes, the assumptions of binomial distribution may deviate or may provide inadequate model. In this Study we propose a new control chart, P-r chart, which is based on regression estimator of proportion based on single auxiliary variable. The performance of the compared with P and Q charts with probability to signal as a performance measure. It has been observed that the proposed chart is superior to the P and Q charts. This study will help quality practitioners to choose an efficient alternative to the classical P and Q charts for monitoring nonconforming units in industrial process.