TABLE OF CONTENTS In an initial stage of production setting, the decision maker often faces the problem of selecting the best manufacturing supplier from several available candidates. There are many factors, such as quality, cost, service and so on, which ought to be considered when selecting the best supplier. Several selection rules have been proposed for selecting the means or variances in the analysis of variance (ANOVA) (see Gibbons, Olkin and Sobel (1977), Gupta and Panchapakesan (1979), Gupta and Huang (1981) more details). The vast majority all of the selection rules is based on the ordered sample variances. A common persistent drawback of these selection rules is that the information available sample data cannot be efficiently used.
As it was mentioned in the earlier Chapters of this book, process capability analysis is applied to determine whether the process capability of a supplier conforms to customer's requirements, by evaluating the process capability index (PCI) to a controlled process.
In the first 10 chapters of this book we have studied the most common PCIs. In the nutshell, PCIs provide common quantitative measures of the manufacturing capability and production quality, to be used by both producer and supplier as a guiding reference when signing a contract. Purchasing personnel may use the PCI to decide whether to accept or reject products provided by suppliers. As we have indicated on numerous (perhaps too numerous!) occasions in this book in practice the process mean and the process variance are usually unknown. In order to calculate the index...
