Operations Management: Processes and Supply Chains, 12th Edition

Selecting a Single-Sampling Plan

Example G.1 raises the question: How can management change the sampling plan to reduce the probability of rejecting good lots and accepting bad lots? To answer this question, let us see how n and c affect the shape of the OC curve. In the Noise King example, a better single-sampling plan would have a lower producer’s risk and a lower consumer’s risk.

Sample Size Effect

What would happen if we increased the sample size to 80 and left the acceptance level, c, unchanged at 1? We can use Table G.1. If the proportion defective of the lot is $p=\text{AQL}=0.01,$ then $np=0.8$ and the probability of acceptance of the lot is only 0.809. Thus, the producer’s risk is 0.191. Similarly, if $p=\text{LTPD}=0.06,$ the probability of ...