Economic design of residuals MEWMA control chart with variable sampling intervals and sample size

AbstractIn order to improve the monitoring efficiency of the multivariable autocorrelation process and reduce the cost of process control, an economic design method of residual Multivariate Exponentially Weighted Moving Average (MEWMA) control charts with variable sample size and sampling intervals (VSSIs) was proposed. First, residual MEWMA control charts with VSSI were designed for monitoring multivariable autocorrelation processes. Second, the economic model of the VSSI residual MEWMA control chart was established, and a data example was given. The optimal design parameters of the control chart were obtained by using a genetic algorithm to minimize the expected cost per unit time. Third, using orthogonal experimental design and regression analysis, a sensitivity analysis of the economic model was carried out to get the relationship between the model parameters and the design parameters of the control chart. Finally, through the optimality analysis, it was verified that the proposed economic model was superior to the models established by the variable sampling intervals strategy and the variable sample size strategy and had less expected cost per unit time.Keywords: Economic designMultivariable autocorrelation processResidual MEWMA control chartSensitivity analysisVariable sampling intervals and sample size Disclosure StatementNo potential conflict of interest was reported by the authors.Additional informationFundingThe work was supported by the National Natural Science Foundation of China Grant (No. 71701188, No. 72261147706, No. 72231005, No. 71871204, No. 71902138), Humanities and Social Sciences Research Program of the Ministry of Education of China Grant (No. 21YJC630151), Natural Science Foundation of Henan Province under Grant (No. 232300420125), Innovative Research Team (in Science and Technology) in University of Henan Province (No. 21IRTSTHN018), Scientific Research Team Plan of Zhengzhou University of Aeronautics (No. 23ZHTD01008), Graduate Education Innovation Program Foundation of Zhengzhou University of Aeronuatics under Grant (No. 2022CX18, No. 2023CX16).