Chain Sampling Scheme under Constant Inspection Errors

摘要

The primary aim of this paper is to extend the inspection error consideration to chain sampling schemes, an area that has not been dealt with in the literature. A mathematical model is developed to investigate the performance of chain sampling schemes under constant inspection errors. Expressions of performance measures, such as operating characteristic function, average total inspection and average outgoing quality, are derived to aid the analysis of a general chain sampling scheme, ChSP-4A (c_1, C_2) r, developed by Frishman. This study reveals that as Type Ⅰ inspection error increases the probability of acceptance will decrease and as Type Ⅱ inspection error increases the acceptance probability will increase. The effect of Type Ⅱ error on the probability of acceptance is very marginal compared with that of Type Ⅰ error, especially when the true fraction non-conforming is small. In addition, the effects of inspection errors can be 'eliminated' by transforming to its equivalent perfect inspection counterpart, hence greatly reducing the complexity of the analysis. The effects of other sampling parameters are also studied to serve as a foundation for future plan designing purposes.