Example of Presummarized Charts
This example creates presummarized charts in two different ways using legacy control charts.
Direct Presummarized Charts
You can create presummarized charts directly by using the legacy Presummarize launch window.
1. Select Help > Sample Data Folder and open Quality Control/Coating.jmp.
2. Select Analyze > Quality and Process > Legacy Control Charts > Presummarize.
3. Select Weight and click Process.
4. Select Sample and click Sample Label.
5. Select both Individual on Group Means and Moving Range on Group Means. The Sample Grouped by Sample Label button is automatically selected when you choose a Sample Label variable.
When using Presummarize charts, you can select either the On Group Means option or the On Group Std Devs option or both. Each option creates two charts (an Individual Measurement, also known as an X chart, and a Moving Range chart) if both IR chart types are selected.
The On Group Means option computes each sample mean and then plots the means and creates an Individual Measurement and a Moving Range chart on the means.
The On Group Std Devs option computes each sample standard deviation and plots the standard deviations as individual points. Individual Measurement and Moving Range charts for the standard deviations then appear.
6. Click OK.
Figure 14.17 Example of Charting Presummarized Data
Although the points for XBar and S charts are the same as the Individual on Group Means and Individual on Group Std Devs charts, the limits are different because they are computed as Individual charts.
Indirect Presummarized Charts
You can also create presummarized charts indirectly by manually creating a summary table and then launching a legacy IR chart.
1. Choose Tables > Summary.
2. Select Sample and click Group.
3. Select Weight, and then click Statistics > Mean and Statistics > Std Dev.
4. Click OK.
5. Select Analyze > Quality and Process > Legacy Control Charts > IR.
6. Select Mean(Weight) and Std Dev(Weight) and click Process.
7. Click OK.
The resulting charts match the presummarized charts.