Characteristics of Sequential Sampling Plans for Attributes: Algorithms for Exact Computing

This paper deals with sequential sampling plans for attributive inspection. With a more general definition any kind of sequential sampling plans are included, especially all curtailed single, double and multiple sampling plans as well as all truncated and non-truncated SPRT’s (sequential probability ratio tests). In a natural way (by direct methods) we find a recursive formula to compute the termination probabilites for acceptance and rejection of the whole lot. Exact computer algorithms are given in a pseudo-programming language to calculate these probabilities in both cases, sampling with and without replacement. Then there is no difficulty to exactly compute the characteristics of any sequential sampling plan like operating characteristic, power function, average sample number or costs, average outgoing quality, average total inspection and so on.