Bivariate dispersion quality control charts
Document Type
Article
Publication Date
1-1-1986
Abstract
A Shewhart procedure is used to simultaneously control the standard deviations of quality characteristics assumed to have a bivariate normal distribution. Following Krishnaiah et al (1963), we use the bivariate chi-square distribution to determine probabilities of out-of-control signals and thus the respective average run lengths (ARLs). Results from an example indicate that for both one-sided and two-sided cases, signals occur only slightly more quickly for changes in the process standard deviations for uncorrelated variables than for correlated variables. © 1986, Taylor & Francis Group, LLC. All rights reserved.
Recommended Citation
Tuprah, Kwami and Woodall, Willian H., "Bivariate dispersion quality control charts" (1986). College of Health, Science, and Technology. 292.
https://digitalcommons.uncfsu.edu/college_health_science_technology/292