Version 17 of JMP introduces many new updates to the CUSUM (cumulative sum) control chart platform. New options include Save Sigma, Save Limits, Get Limits, and Platform Preferences. Also, test failures have been added to the summary table.
Example
Open Engine Temperature Sensor.jmp found in the Quality Control folder and create a CUSUM chart.
dt=Open("$SAMPLE_DATA/Quality Control/Engine Temperature Sensor.jmp");
obj=dt<<CUSUM control="" chart=""></CUSUM>
This table contains temperature measurements from an engine thermostat. You wish to detect small shifts in the temperature of an engine.
Image 1Image 1
Save Sigma
Version 17 introduces the ability to Save Sigma. Click on the red triangle next to CUSUM Control Chart - Y and select Save Sigma. When you look at the data table again, you will see that a column property has been added to Y. Opening Column Info for Y, shows that a sigma property has been saved with a value of 10. This is the same value found in the control panel for sigma in Image 1.
Image 2Image 2
Save Limits
Another new option for JMP 17, is Save Limits. You can choose to Save Limits->in Column or Save Limits -> in New Table. For this example, click on the red triangle next to CUSUM Control Chart - Y and select Save Limits -> in New Table. This creates a new limits table containing the H, K, Std Dev, Mean, and Head Start values.
Image 3Image 3
Get Limits
Get Limits is also new in JMP 17. We would like to apply the limits table created above to a new data table. You can accomplish this by running the following:
dt2=New Table( "Engine Temperature Sensor 2",
Add Rows( 20 ),
New Column( "Y",
Numeric,
"Continuous",
Format( "Best", 12 ),
Set Selected,
Set Values(
[113.025563936654, 113.698535336229, 123.939789495525, 123.938376104238,
105.94054113345, 112.790628740325, 124.915268095181, 87.3802804399079,
105.65037516109, 110.883581091859, 112.564388652434, 112.149860487558,
119.262393797902, 104.880299715207, 124.419531558804, 112.712922022065,
119.787992583872, 110.651809706602, 97.9316474975944, 121.797446301115]
)
)
);
obj2=dt2<<CUSUM control="" chart=""></CUSUM>
Click on the red triangle next to CUSUM Control Chart – Y and select Get Limits. Pick the newly created limits table.
Image 4Image 4
The control panel on the left is updated to use the values found in the limits table (Image 3 above).
Platform Preferences
The Platform Preferences option in the red triangle menu is a new option for all platforms. This option contains a submenu with Go to and Save Changes to. For this example, the Go to option will take you to the platform preferences for CUSUM Control Chart. The Save Changes to option will open a dialog that allows you to alter any non-default platform preferences for CUSUM control charts.
Test failures saved to the summary table
The last new addition for CUSUM charts in Version 17 includes test failure information now being saved to the summary table. First you must turn on tests. From the red triangle, select Test Beyond Limits. Next select Save Summaries from the red triangle menu. A new column has been added to the summary table titled “Test Failures”. This column contains information about which samples have failed Test Beyond Limits.
Conclusion
Many new features have been added to CUSUM control charts in Version 17 of JMP. New options include Save Sigma, Save Limits, Get Limits, and Platform Preferences. Also, information about test failures are now present in the summary table. These features yield a richer environment in which the user has more control over chart display and construction.
