Accession Number:

ADA083032

Title:

The Use of R and S2 Charts Under Nonstandard Conditions.

Descriptive Note:

Research rept.,

Corporate Author:

VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG

Personal Author(s):

Report Date:

1980-03-01

Pagination or Media Count:

31.0

Abstract:

R and S-squared charts for monitoring the variability of a process are studied when the control variance, sigma sub 0 squared is unknown, when observations are non-Gaussian, and when the process drifts. Geometric bounds on run-length distributions for the R and S-squared charts are given for all underlying distributions when sigma sub 0 squared is estimated in a base period. Similar bounds apply in the case of a drifting process, the notion of which is developed rigorously. It is shown that normal-theory properties of these charts hold exactly for every spherical process when a suitable estimate for sigma sub 0 squared is used. Run-length distributions otherwise are shown to be ordered stochastically given a peakedness ordering on the underlying spherical processes. Author

Subject Categories:

  • Statistics and Probability

Distribution Statement:

APPROVED FOR PUBLIC RELEASE