Design of Minimum Average Total Inspection Sampling Plans

ABSTRACT

The design of a sampling inspection plan that involves the minimum average total inspection at a given quality level is of practical interest. The acceptance sampling literature suggests that a specific type of double sampling plan be used for this purpose. This double sampling plan allows no non conforming units in the first stage and no more than one non conforming unit in the second stage of inspection. In this note it is argued that the zero acceptance number single sampling plan is still preferred to a double sampling plan for achieving minimum average total inspection at a given point on the Operating Characteristic (OC) curve. A theoretical discussion on the broken sample size is provided for justifying the choice of the single sampling plan.

Key Words:

• Attribute inspection
• Average total inspection
• OC function
• Single and double sampling plans
• Zero acceptance number

Mathematics Subject Classification:

• 62-XX
• 62P30

Acknowledgment

The author is thankful to the referees for comments, particularly the suggestion to perform a simulation and the example.