Dependent-deferred state attribute acceptance sampling

This research is concerned with attribute sampling inspection procedures in which the decision criterion for each lot dictates one of three dispositions; (1) accept the lot, (2) reject the lot, or (3) conditionally accept or reject the lot based on the disposition of other related lots. These sampling procedures will supplement several types of dependent state sampling procedures developed within research years. The primary objective of most dependent state sampling procedures was to give consideration to the quality of previously inspected lots in the judgement criterion of a current lot, with respect to acceptance or rejection of this lot. Deferred state sampling procedures, on the other hand, give consideration to the quality of future lots. There are three basic sampling procedures presented which are called: fixed deferred state, multiple deferred state, and dependent-deferred state. Al three sampling procedures are shown to possess appealing properties with respect to their operating characteristic curves. Comparisons of the above plans with single, double, and sequential sampling indicated that adequate consumer and producer protection can be provided, while reducing the sample size. This savings in sampling costs is the primary advantage of deferred state sampling procedures over classical sampling procedures. The primary advantage of deferred state sampling procedures over dependent state sampling procedures is that quality degradations are more readily identified by deferring conditional decisions. That is, a deferred state sampling procedure is less likely to accept a lot immediately following a degradation of process quality than a comparable dependent state sampling procedure