Title: Combined EWMA-mixed EWMA CUSUM schemes for monitoring the process mean

Authors: Dushyant Tyagi; Himani Shonik; Vikas Saxena

Addresses: Dr. Shakuntala Mishra National Rehabilitation University, Mohan Rd, Lucknow, Uttar Pradesh, 226017, India ' G.L. Bajaj Institute of Management and Research, Greater Noida, India ' National Institute of Food Technology Entrepreneurship and Management (NIFTEM), 97, Niftem Rd, HSIIDC, Industrial Estate, Kundli, Sonipat, Haryana, 131028, India

Abstract: Control charts are the most popular tools of statistical quality control to detect shifts in any operational process. Cumulative sum (CUSUM) and exponentially weighted moving average (EWMA) charts are used to detect small to moderate shifts, but both have their own limitations. Abbas et al. (2012) presented the mixed EWMA CUSUM (MEC) scheme, wherein he applied CUSUM chart on EWMA statistic. In this paper, we have proposed a combination of EWMA and MEC charts. The performance of the proposed chart is evaluated in terms of the average run length (ARL) and standard deviation of run length (SDRL) values. After comparing the proposed scheme with some existing schemes by ARL ratio, the results show that the performance of the proposed scheme is superior to other schemes.

Keywords: average runs length; standard deviation of runs length; Monte Carlo simulation; statistical process control; cumulative sum scheme; exponentially weighted moving average scheme; ARL ratio; small shifts.

DOI: 10.1504/IJPQM.2025.148950

International Journal of Productivity and Quality Management, 2025 Vol.46 No.2, pp.191 - 210

Received: 13 Sep 2022
Accepted: 03 Aug 2023
Published online: 06 Oct 2025 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article