Estimating process capability index C_pk: classical approach versus Bayesian approach

Abstract

Process capability index C_pk has been the most popular one used in the manufacturing industry dealing with problems of measuring reproduction capability of processes to enhance product development with very low fraction of defectives. In the manufacturing industry, lower confidence bound (LCB) estimates the minimum process capability providing pivotal information for quality engineers to monitoring the process and assessing process performance for quality assurance. The main objective of this paper is to compare and contrast the LCBs on C_pk using two approaches, Classical method and Bayesian method.

Keywords:

• Bayesian method
• credible interval
• Classical method
• lower confidence bound
• process capability index