Multiple dependent state sampling plans for lot acceptance based on measurement data

摘要

To propose a multiple dependent (as deferred) state sampling plan by variables for the inspection of normally distributed quality characteristics. Acceptance sampling is a statistical tool used to make decisions concerning whether or not a lot of products should be released for consumer use. Variable sampling plans constitute one of the major areas of the theory and practice of acceptance sampling. The primary advantage of the variables sampling plan is that the same operating characteristic (OC) curve can be obtained with a smaller sample size than would be required by an attributes sampling plan. When destructive testing is employed, variables sampling is particularly useful in reducing the costs of inspection. Owen (Ref. 1) developed variables sampling plans based on the normal distribution when the standard deviation of the process is unknown. Hamaker (Ref. 2) has given a procedure of finding the parameters for unknown sigma variables sampling plans from known sigma variables sampling plans. Bravo and Wetherill (Ref. 3) developed a method for designing double sampling plans by variables with OC curves matching with the OC curves of the equivalent single sampling plans. Schilling (Ref. 4) has written an exclusive book on acceptance sampling which also deals with conventional variables sampling plans. Baillie (Ref. 5) developed tables for double variables sampling plans when the process standard deviation is unknown.