Communications for Statistical Applications and Methods

The Korean Statistical Society (한국통계학회)
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A Modified Definition on the Process Capability Index Cpk Based on Median

  • Park, Hyo-Il (Department of Statistics, Chongju University)
  • Received : 20110300
  • Accepted : 20110400
  • Published : 2011.07.31
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Abstract

This study proposes a modified definition about $C_{pk}$ based on median as the centering parameter in order to more easily control the process since the mean does not represent any quantile of the asymmetric process distribution. Then we consider an estimate and derive the asymptotic normality for the estimate of the modified $C_{pk}$. In addition, we provide an example with asymmetric distributions and discuss the estimation for the limiting variance that are followed by some concluding remarks.

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References

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