The design of EWMA control chart for average with type-I censored data

Purpose - The purpose of this paper is to establish an exponentially weighted moving average (EWMA) control chart for monitoring the mean level of Gompertz lifetimes with type-I censoring. Design/methodology/approach - The proposed control chart is developed based on the conditional expected values (CEVs). The control limits are determined numerically with an algorithm. Findings - Compared with the EWMA CEV control charts of Zhang and Chen, numerical results indicate that the proposed control chart has good performance to detect mean shifts for Gompertz lifetimes either in decrease or in larger increase with type-I censoring in terms of the average run length (ARL). Originality/value -The paper shows that, based on the proposed method, practitioners can monitor the mean level of Gompertz lifetimes via an EWMA CEV control chart with type-I censoring.