A study on the performances of the run sum X̄ chart under the gamma process Kai Le Goh, Wei Lin Teoh, Zhi Lin Chong, Kai Lin Ong and Laila El-Ghandour ITM Web Conf., 67 (2024) 01002 Published online: 21 August 2024 DOI: 10.1051/itmconf/20246701002