SPC Procedure
SCHART Statement
SCHART < / options>;
The SCHART statement produces control charts for subgroup standard deviations. Table 11 lists the options that you can specify in an SCHART statement. For detailed descriptions of these options, see the section Dictionary of Options.
Table 11: SCHART Statement Options
| Option | Description |
|---|---|
| ALLN | Includes all subgroups in the analysis, regardless of sample size |
| CIINDICES | Computes capability index confidence limits |
| EXCHART | Produces results only for charts in which exceptions occur |
| LIMITN= | Specifies the nominal sample size for fixed control limits |
| NO3SIGMACHECK | Enables tests for special causes to be applied when control limits other than |
| NOPRINT | Suppresses ODS output |
| OUTLIMITS= | Creates an output data table that contains control limits |
| OUTTABLE= | Creates an output data table that contains subgroup summary statistics and control limits |
| SIGMAS= | Specifies the width of the control limits in terms of a multiple of the standard error of the subgroup summary statistic |
| SMETHOD= | Specifies the method of estimating the process standard deviation |
| SPECS= | Specifies an input data table that contains process specification limits and computes process capability indices |
| TEST2RUN= | Specifies the length of the pattern for Test 2 |
| TEST3RUN= | Specifies the length of the pattern for Test 3 |
| TESTNSTD | Applies tests for special causes to standardized chart statistics |
| TESTOVERLAP | Performs tests for special causes on overlapping patterns of points |
| TESTS2= | Requests tests for special causes for the s chart |
Last updated: May 14, 2026