When you are working with subgrouped data, it can be helpful to accompany a cusum chart for means with a Shewhart s chart for monitoring the variability of the process. This example creates this ...

A cusum chart is more efficient for detecting small shifts in the process mean, in particular, shifts of 0.5 to 2 standard deviations from the target mean (refer to Montgomery 1996). Lucas (1976) ...

Background: CUSUM analysis is an analytic tool for monitoring institutional quality and clinical outcomes. CUSUM is a summative plot of an event that occurs over time. The slope that is generated can ...