Performance Evaluation of Extended EWMA Chart for AR Model with Exogenous Variables

Totsaporn Muangngam, Yupaporn Areepong, Saowanit Sukparungsee

Abstract


The extended exponentially weighted moving average (Extended EWMA) control chart is an effective statistical process control method for monitoring and identifying shifts in process mean, particularly when dealing with autocorrelated data. One key performance measure used to evaluate the capability of control charts in detecting changes is the average run length (ARL). The primary goal of this study is to present the explicit formulas for calculating the ARL of the extended EWMA control chart for autoregressive models with exogenous variables (ARX) and exponential white noise. Another purpose is to compare the performance of the extended EWMA and the classical EWMA control charts under various conditions. The explicit formulas are derived from the ARL integral equation, which is expressed by the Fredholm integral equation. The accuracy of the exact solutions has been verified using the numerical integral equation (NIE) methods that employ four different composite quadrature rules. The result shows that the ARL values obtained from both methods are similar, and the computation time for the proposed explicit formulas is less than 0.001 second. In comparing the two control charts, it is evident that the extended EWMA control chart outperforms the traditional control chart in detecting shifts in the process mean, as confirmed by various overall performance criteria. Additionally, two real datasets, namely SCB stock price and GDP percentage expansions, are applied to demonstrate the effectiveness of the relevant control charts.

 

Doi: 10.28991/HIJ-2024-05-04-03

Full Text: PDF


Keywords


Average Run Length; Extended EWMA Chart; Explicit Formula; Autoregressive with Exogenous Variables.

References


Shewhart, W. A. (1930). Economic quality control of manufactured product 1. Bell System Technical Journal, 9(2), 364-389. doi:10.1002/j.1538-7305.1930.tb00373.x.

Page, E. S. (1954). Continuous Inspection Schemes. Biometrika, 41(1/2), 100-115. doi:10.2307/2333009.

Roberts, S. W. (1959). Control Chart Tests Based on Geometric Moving Averages. Technometrics, 1(3), 239. doi:10.2307/1266443.

Patel, A. K., & Divecha, J. (2011). Modified exponentially weighted moving average (EWMA) control chart for an analytical process data. Journal of Chemical Engineering and Materials Science, 2(1), 12–20.

Khan, N., McClean, S., Zhang, S., & Nugent, C. (2023). Performance evaluation of multivariate statistical techniques using edge-enabled optimisation for change detection in activity monitoring. Journal of Cloud Computing, 12(1), 91. doi:10.1186/s13677-023-00467-x.

Abbas, N., Riaz, M., & Does, R. J. M. M. (2013). Mixed exponentially weighted moving average-cumulative sum charts for process monitoring. Quality and Reliability Engineering International, 29(3), 345–356. doi:10.1002/qre.1385.

Naveed, M., Azam, M., Khan, N., & Aslam, M. (2018). Design of a Control Chart Using Extended EWMA Statistic. Technologies, 6(4), 108–122. doi:10.3390/technologies6040108.

Zahid, R., Noor-ul-Amin, M., Khan, I., AlQahtani, S. A., Pathak, P. K., & Rahimi, J. (2023). Combination of memory type ratio and product estimators under extended EWMA statistic with application to wheat production. Scientific Reports, 13(1), 13547. doi:10.1038/s41598-023-40687-4.

Jawad Mirza, M., Hashmi, S., Thomas Mwakudisa, M., Safariyan, A., Naghmi Habibullah, S., & Noor-ul-Amin, M. (2024). Performance evaluation of extended EWMA control chart in the presence of measurement error. Communications in Statistics: Simulation and Computation, 1–16. doi:10.1080/03610918.2024.2408624.

Alwan, L. C. (1992). Effects of autocorrelation on control chart performance. Communications in Statistics - Theory and Methods, 21(4), 1025–1049. doi:10.1080/03610929208830829.

Reynolds, M. R., Arnold, J. C., & Baik, J. W. (1996). Variable sampling interval X charts in the presence of correlation. Journal of Quality Technology, 28(1), 12–30. doi:10.1080/00224065.1996.11979633.

Zhang, N. F. (1997). Detection capability of residual control chart for stationary process data. Journal of Applied Statistics, 24(4), 475–492. doi:10.1080/02664769723657.

Tyagi, D., & Yadav, V. (2024). Combined Quality Control Scheme for Monitoring Auto correlated Process. Thailand Statistician, 22(4), 986–1005.

Maçaira, P. M., Tavares Thomé, A. M., Cyrino Oliveira, F. L., & Carvalho Ferrer, A. L. (2018). Time series analysis with explanatory variables: A systematic literature review. Environmental Modelling and Software, 107, 199–209. doi:10.1016/j.envsoft.2018.06.004.

Suparman. (2018). A new estimation procedure using a reversible jump MCMC algorithm for AR models of exponential white noise. International Journal of GEOMATE, 15(49), 85–91. doi:10.21660/2018.49.3622.

Champ, C. W., & Ritrdon, S. E. (1991). A Comparison of the Markov Chain and the Integral Equation Approaches for Evaluating the Run Length Distribution of Quality Control Charts. Communications in Statistics - Simulation and Computation, 20(1), 191–204. doi:10.1080/03610919108812948.

Paichit, P. (2016). Average run length of control chart for ARX(1) process with exponential white noise. Global Journal of Pure and Applied Mathematics, 12(3), 2143–2153.

Phanyaem, S. (2022). Explicit Formulas and Numerical Integral Equation of ARL for SARX(P,r)L Model Based on CUSUM Chart. Mathematics and Statistics, 10(1), 88–99. doi:10.13189/ms.2022.100107.

Suriyakat, W., & Petcharat, K. (2022). Exact Run Length Computation on EWMA Control Chart for Stationary Moving Average Process with Exogenous Variables. Mathematics and Statistics, 10(3), 624–635. doi:10.13189/ms.2022.100319.

Supharakonsakun, Y. (2021). Comparing the effectiveness of statistical control charts for monitoring a change in process mean. Engineering Letters, 29(3), 1108–1114.

Karoon, K., Areepong, Y., & Sukparungsee, S. (2023). Trend Autoregressive Model Exact Run Length Evaluation on a Two-Sided Extended EWMA Chart. Computer Systems Science and Engineering, 44(2), 1143–1160. doi:10.32604/csse.2023.025420.

Zhang, L., Suraphee, S., & Busababodhin, P. (2023). Derivation of Explicit Formulae for Performance Measures of CUSUM Control Chart for SMA(Q)s Model with Exponential White Noise. Lobachevskii Journal of Mathematics, 44(9), 3902–3913. doi:10.1134/S1995080223090457.

Peerajit, W. (2024). Determining the ARL for a Shift in the Mean of a Long-Memory ARFIMA(1, d, 1)(1, D, 1)s Process with Exponential White Noise Running on a CUSUM Control Chart. Thailand Statistician, 22(2), 407–429.

Sunthornwat, R., Sukparungsee, S., & Areepong, Y. (2024). The Development and Evaluation of Homogenously Weighted Moving Average Control Chart based on an Autoregressive Process. HighTech and Innovation Journal, 5(1), 16–35. doi:10.28991/HIJ-2024-05-01-02.

Phanthuna, P., Areepong, Y., & Sukparungsee, S. (2024). Performance Measurement of a DMEWMA Control Chart on an AR(p) Model with Exponential White Noise. Applied Science and Engineering Progress, 17(3), 7088. doi:10.14416/j.asep.2023.10.005.

Phanyaem, S. (2024). Precise Average Run Length of an Exponentially Weighted Moving Average Control Chart for Time Series Model. Thailand Statistician, 22(4), 909–925.


Full Text: PDF

DOI: 10.28991/HIJ-2024-05-04-03

Refbacks

  • There are currently no refbacks.


Copyright (c) 2024 Totsaporn Muangngam, Yupaporn Areepong, Saowanit Sukparungsee