On the asymptotic correlationship for some process capability indices Ĉp, Ĉpk and Ĉpm under bivariate normal distribution Cho, Joong-Jae; Park, Hyo-Il;
The process capability index is used to determine whether a production process is capable of producing items within a specified tolerance. Some process capability indices , and have been of particular interest as useful management tools for tracking process performance. Most evaluations on process capability indices focus on statistical estimation and test of hypothesis. It is necessary to investigate their asymptotic correlationship among basic estimators , and of process capability indices , and . In this paper, we study their asymptotic correlationship for three process capability indices , and under bivariate normal distribution BN(). With some nonnormal processes, the asymptotic correlation coefficient of any two respective process capability index estimators could be established.
asymptotic correlation coefficient;bivariate normal distribution;limiting distribution;process capability index;process performance;
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