Phase-I design structure of Bayesian variance chart

Cogent Mathematics

Aamir Saghir¹ 

[1] Mirpur University of Science and Technology (MUST);

关键词: process control;    variance Chart;    posterior distribution;    OC function;    predictive limits;   

DOI  :  10.1080/23311835.2016.1172403

来源: DOAJ

【 摘 要 】

This article develops a new design structure for S2-Chart, namely Bayesian variance chart, in Phase-I analysis assuming the normality of the quality characteristic to incorporate the parameter uncertainty. Our approach consists of two stages: (i) construction of the control limits for S2-Chart and (ii) performance evaluation of the proposed control limits. The comparison of the proposed design structure with the frequentist design structure of S2-Chart is examined in terms of (i) width of control region and (ii) OC curves when the process variance goes out of control. It is observed that the proposed Phase-I S2-Chart is more efficient than the frequentist S2-Chart in discriminatory power of detecting a shift in the process dispersion. When the process variance is in-control (after implementation of Bayesian variance chart), then the control limits for $ \bar{X} $-Chart using in-control standard deviation are also given here for monitoring unknown mean under unknown standard deviation case.

【 授权许可】

Unknown