Evaluation of production yield for process selection

Process evaluation is a common yet important problem in industry. Among the key measurements such as quality, processing time, cost, and robustness, production yield is one of the fundamental criteria frequently adopted to evaluate the quality level of a process. A process with high yield is better capable of producing products meeting the requirements preset by customers. However, general evaluation procedures that count the number of defectives become inefficient especially when yield rates are high. This paper considers the processes evaluation problem by comparing the yield index S_pk of two production lines with high quality. An effective and efficient approach is proposed to solve the problem. The analytical method examines the difference of two yields. The approach requires small sample sizes but sensitively distinguishes production yields. The results provide useful information to practitioners.