A CUSUM Chart for Monitoring an Attribute Event

This article proposes a CUSUM chart, called the R-CUSUM chart, for the monitoring of a negative event. This chart is developed using a Markov model. It is able to check both the time interval (T) between occurrences of the event and the size (C) of each occurrence. Our studies show that the R-CUSUM chart is more effective than the existing R (=C/T) chart for event monitoring. The improvement in performance is achieved because of the use of the CUSUM feature. The R-CUSUM chart can be applied in manufacturing systems, and especially in non-manufacturing sectors (e.g., health care industry, disaster management, and security control).