For control charts, use OC curves to explore how chart parameter settings impact β, the probability of failing to detect a specified shift of interest. Use the text boxes, sample size slider, or the LCL, Shift, Center, and UCL handles on the OC curve to set and adjust chart parameters. The chart parameters are as follows:
Lower Control Limit
Specifies the lower control limit from your control chart.
Upper Control Limit
Specifics the upper control limit from your control chart.
Center Line
Specifics the center line from your control chart.
Sigma
(Available only for XBar charts.) Specifies your control chart sigma.
Sample Size
(Not available for C charts.) Specifies the sample size used for your control chart measure.
Shift
Specifies the shift to detect.
Probability of Detection
Specifies the probability of detecting (also known as 1-β) the specified shift given the control chart specifications. The probability of detection updates as specifications are changed.