Publication date: 03/23/2021

OC Curves for Control Chart Options

For control charts, you can use OC curves to explore how specifications impact β, which is the probability of failing to detect a specified shift of interest. Use the text boxes, sliders, or the LCL, Shift, and UCL handles on the OC curve to set and adjust specifications. The specifications 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.

Sample Size

(Not available for C charts.) Specifies the sample size used for your control chart measure.

Sigma

(Available only for XBar charts.) Specifies your control chart sigma.

Shift

Specifies the shift to detect.

Beta

Specifies the probability of failing to detect the specified shift given the control chart specifications. Beta updates as the specifications are changed.

Want more information? Have questions? Get answers in the JMP User Community (community.jmp.com).