Running the Analysis

  1. To run a control charts analysis, from the menus choose:

    Analyze > Quality Control > Control Charts...

    Figure 1. Control Charts dialog box
    Control Charts dialog box
  2. Click Define.
    Figure 2. X-Bar, R, s: Cases Are Units dialog box
    X-Bar, R, s: Cases Are Units dialog box
  3. Select pH level as the process measurement variable.
  4. Select Time of measurement as the subgroup definition variable.
  5. Click Statistics.
    Figure 3. Statistics dialog box
    Statistics dialog box
  6. Type 5.5 as the upper specification limit (USL).
  7. Type 4.5 as the lower specification limit (LSL).
  8. Type 5.0 as the target value.
  9. Select CP, CpU, CpL, K, CpM, and Z-out in the Process Capability Indices group.
  10. Select PP, PpU, PpL, PpM, and Z-out in the Process Performance Indices group.
  11. Select Actual % outside specification limits.
  12. Click Continue.
  13. Click Control Rules in the X-Bar, R, s: Cases Are Units dialog box.
    Figure 4. Control Rules dialog box
    Control Rules dialog box
  14. Choose Select all control rules.
  15. Click Continue.
  16. Click OK in the X-Bar, R, s: Cases Are Units dialog box.

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