Attribute Charts Results - Charts Tab
Control Charts for Variables vs. Charts for Attributes
Select the Charts tab of the Results dialog box to access the options described here.
Descriptives
Click this button to create a spreadsheet of descriptive statistics (number defective, rate defective, binomial counts, binomial proportions). Samples that fall outside the control limits will be highlighted.
Check alarms
Click this button to create a spreadsheet with the current summary of possible control chart violations (quality problems) that may trigger alarms. Statistica will check and report all (potential) alarms as described on the Options dialog box - Alarm tab regardless of whether checking of specific violations (a specific alarm) is requested. The results spreadsheet will indicate in the column headers which violations are currently being monitored:
The label Not Applicable means that the respective type of violation is not applicable to the current type of chart or that the specifications for the current chart are such that the respective type of violation is not applicable (no warning limits were specified).
The label Not Checked means that the respective type of violation is not currently being monitored by the program (see also the documentation for the Options dialog box - Alarm tab for details).
This spreadsheet provides a useful quick summary of the types of problems that may be evident in the current control chart.
OC Curve
Click this button to display an Operating characteristic curve chart. We can determine the beta (b) probability of not detecting a shift in the process mean (rate defective in the U chart) from target specification to the respective values on the X axis. Also shown in the plot are the respective curves for larger and smaller sample sizes (these will not be shown for the C chart). A normal approximation is used to calculate beta for P and Np charts.