Properties of T2 Charts in Monitoring Process Means.
Abstract
Hotellings T squared and related charts are studied in monitoring the means of a multidimensional production process. The T squared chart is shown to be optimal in a class of procedures in that it signals more quickly than other procedures in the class when the process is not in control. Nonstandard properties of the distributions of run lengths of these charts are studied when (i) certain parameters are estimated in a base and modified procedures are followed using these estimates, (ii) the process is a drifting process, and (iii) the assumption of independent Gaussian vector observations is replaced by the assumption that the observations are generated from a spherical process. For these cases stochastic bounds on the actual run-length distributions are given in terms of geometric distributions, and certain monotone properties of run lengths are established under driftings. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1981
- Accession Number
- ADA103636
Entities
People
- D. R. Jensen
- Y. V. Hui
Organizations
- Virginia Tech