Chapter 4
Shewhart Control Charts
Create Variable and Attribute Control Charts
A control chart is a graphical and analytic tool for monitoring process variation. The natural variation in a process can be quantified using a set of control limits. Control limits help distinguish common-cause variation from special-cause variation. Typically, action is taken to eliminate special-cause variation and bring the process back in control. It is also important to quantify the common-cause variation in a process, as this determines process capability.
The Control Chart platform in JMP provides a variety of control charts, as well as run charts. To support process improvement initiatives, most of the control chart options display separate control charts for different phases of a project on the same chart.
• Run Chart
• X-, R-, and S-charts
• Individual and Moving Range Charts
• p-, np-, c-, and u-charts
• UWMA and EWMA Charts
• CUSUM Charts
• Presummarize, Levey-Jennings, and Multivariate Control Charts
• Phase Control Charts for X-, R-, S-, IR-, p-, np-, c-, u-, Presummarize, and Levey-Jennings Charts.
Figure 4.1 Control Chart Example