Skip to main content
Article
Design Strategies for Individual and Moving Range Control Charts
Journal of Quality Technology
  • Steve E. Rigdon, Southern Illinois University Edwardsville
  • Emma N. Cruthis, Central Illinois Public Service Co.
  • Charles W. Champ, Georgia Southern University
Document Type
Article
Publication Date
1-1-1994
Disciplines
Abstract

Individuals and moving range charts are often used when production volume is too low to justify rational subgrouping. This article considers several aspects of the design strategy for these charts. We have found that the X chart alone is nearly as efficient as the combined X-MR chart for detecting changes in the process variability. We recommend, however, that the control limits on the individuals chart be based on a short-term estimate of the process variability, such as the moving range, rather than on a long term estimate, such as the sample standard deviation of the process. We also consider the effects of nonnormality and autocorrelation.

Citation Information
Steve E. Rigdon, Emma N. Cruthis and Charles W. Champ. "Design Strategies for Individual and Moving Range Control Charts" Journal of Quality Technology Vol. 26 Iss. 4 (1994) p. 274 - 287 ISSN: 0022-4065
Available at: http://works.bepress.com/charles_champ/25/