Lot acceptance and compliance testing using the sample mean and an extremum

摘要

In deciding whether to accept a lot of material in some industrial applications,sometimes the sample mean and minimum (or maximum) is compared to reference values.The exact joint cdf of an extremum and the mean of a normal sample is complicated.It is then difficult to base acceptance criteria on statistical considerations.An approximation for this joint cdf based on the saddlepoint method is developed,which is very accurate and straightforward to compute.This approximation can be used to establish statistically based acceptance criteria or to evaluate the performance of sampling plans based on criteria derived in other ways.Examples are presented illustrating these uses.(6 refs.)