Encyclopedia of Statistics in Quality and Reliability
Abstract
Chapter Summary: Control charts for controlling the process mean are affected by changes in the process standard deviation. Therefore it is important to also control the process standard deviation. Various control charting methods have been developed for this purpose. Two commonly recommended statistical methods for controlling the process standard deviation are the moving range (MR) and the range (R) charts. The designs of MR and R charts are discussed in this article and each is illustrated with an example.
This paper has been withdrawn.
