Journal of Korean Society for Quality Management (품질경영학회지)

Korean Society for Quality Management (한국품질경영학회)
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Better Statistical Test for Process Capability Index $C_p$

공정능력지수 $C_p$에 대한 효율적인 가설검정

  • Cho, Joong-Jae (Department of Information and Statistics, Chungbuk National University) ;
  • Lim, Soo-Duck (Department of Information and Statistics, Chungbuk National University)
  • 조중재 (충북대학교 자연과학대학 정보통계학과) ;
  • 임수덕 (충북대학교 자연과학대학 정보통계학과)
  • Published : 2006.09.30
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Abstract

The process capability indices are widely used to measure the capability of the process to manufacture items within the specified tolerance. Most evaluations on process capability indices focus on point estimates, which may result in unreliable assessments of process performance. The index $C_p$ has been widely used in various industries to assess process performance. In this paper, we propose new testing procedure on assessing $C_p$ index for practitioners to use in determining whether a given process is capable. The provided approach is easy to use and the decision making is more reliable. Whether a process is clearly normal or nonnormal, our bootstrap testing procedure could be applied effectively without the complexity of calculation. A numerical result based on the proposed approach is illustrated.

Keywords

References

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