Probabilities of Failure in Mixed Acceptance Sampling Schemes

Mixed acceptance sampling schemes are commonly used for consumer protection. In a typical application, a sample is taken from a product lot and tested to check that the average value of the sample is not less than the labelled net content, and that there is no 'unreasonable' deficiency in any individual item. Exact and approximate expressions are obtained for the probabilities of failure or success under such schemes and under a variety of conditions.