This global setting sets the estimation method for each type of control chart. Select
Analysis
Preferences
in the
Engineering portal, then navigate to Control
Charts.
The available estimation methods depend on the type of control chart and the subgroup size.
Control chart | Estimation methods |
---|---|
I-MR Chart |
|
Xbar-R Chart |
|
Xbar-S Chart |
|
I-MR-R/S Chart | For between-subgroup standard deviation:
|
EWMA Chart | When subgroup size > 1:
|
This global setting sets the default settings for each control chart test. Select
Analysis
Preferences
in the
Engineering portal, then navigate to .
Use the tests to determine which observations to investigate and to identify the specific patterns and trends in your data. By default, Real-Time SPC uses only Test 1. Select additional tests based on company or industry standards.
This global setting sets the default settings for the calculation of control limits.
Select Analysis
Preferences
in the
Engineering portal, then navigate to .
For new control charts, the center line and control limits are calculated from the data. You can specify the moving data range for these calculations.
For continuous data, the default is 100 observations. For attribute data, the default is 25 subgroups. Change these settings if you want to include more or less data in the calculations.
After the center line and control limits of a control chart have been calculated, they are set and locked. These lines will remain until a new calculation is initiated. For more information on control limit options, go to Control limits.
This global setting sets the maximum number of subgroups that display on each control
chart. Select Analysis
Preferences
in the
Engineering portal, then navigate to .
When All subgroups is selected, the control chart displays the maximum number of subgroups per the global setting maximum.
For more information on other specific control chart display options, go to Control chart display options.