Estimating Nonconformity Rates in c-Defect Sampling

Abstract

An estimator is presented for the outgoing quality under zero-defect sampling and similar inspection plans. The method does not depend on knowing the distribution of the incoming lot quality and can be applied with equal or unequal lot sizes. Confidence intervals can be calculated. A criterion is derived to test whether the sample size is optimal given the costs of production, inspection, and accepting nonconforming units.