Journal of Korean Institute of Industrial Engineers (대한산업공학회지)

Korean Institute of Industrial Engineers (대한산업공학회)
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Multivariate Process Capability Indices for Skewed Populations with Weighted Standard Deviations

가중표준편차를 이용한 비대칭 모집단에 대한 다변량 공정능력지수

  • Jang, Young Soon (LG CNS Co., Ltd. Consulting SSU) ;
  • Bai, Do Sun (Department ofIndustrial Engineering, Korea Advanced Institute of Science and Technology)
  • Published : 2003.06.30
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Abstract

This paper proposes multivariate process capability indices (PCIs) for skewed populations using $T^2$rand modified process region approaches. The proposed methods are based on the multivariate version of a weighted standard deviation method which adjusts the variance-covariance matrix of quality characteristics and approximates the probability density function using several multivariate Journal distributions with the adjusted variance-covariance matrix. Performance of the proposed PCIs is investigated using Monte Carlo simulation, and finite sample properties of the estimators are studied by means of relative bias and mean square error.

Keywords

References

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