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CCHART Statement |
Variable | Description |
_ALPHA_ | probability () of exceeding limits |
_C_ | value of central line on c chart ( or n_{i}u_{0}) |
_INDEX_ | optional identifier for the control limits specified with the OUTINDEX= option |
_LCLC_ | lower control limit for number of nonconformities |
_LIMITN_ | sample size associated with the control limits |
_SIGMAS_ | multiple (k) of standard error of c_{i} |
_SUBGRP_ | subgroup-variable specified in the CCHART statement |
_TYPE_ | type (estimate or standard value) of _U_ |
_U_ | average number of nonconformities per unit ( or u_{0}) |
_UCLC_ | upper control limit for number of nonconformities |
_VAR_ | process specified in the CCHART statement |
Notes:
The OUTLIMITS= data set contains one observation for each process specified in the CCHART statement. For an example, see "Saving Control Limits" .
Given a process name that contains eight characters, the procedure first shortens the name to its first four characters and its last three characters, and then it adds the suffix. For example, the procedure shortens the process NDEFECTS to NDEFCTS before adding the suffix.
Subgroup summary variables are created for each process
specified in the CCHART statement.
For example, consider the following statements:
proc shewhart data=fabric; cchart (flaws ndefects)*lot / outhistory=summary; run;
The data set SUMMARY contains variables
named LOT, FLAWSU, FLAWSN, NDEFCTSU, and NDEFCTSN.
Additionally, the following variables, if specified, are included:
For an example that creates an OUTHISTORY= data set, see "Saving Nonconformities per Unit" . Note that an OUTHISTORY= data set created with the CCHART statement can be used as a HISTORY= data set by either the CCHART statement or the UCHART statement.
Variable | Description |
_ALPHA_ | probability () of exceeding control limits |
_EXLIM_ | control limit exceeded on c chart |
_LCLC_ | lower control limit for number of nonconformities |
_LIMITN_ | nominal sample size associated with the control limits |
_SIGMAS_ | multiple (k) of the standard error associated with control limits |
subgroup | values of the subgroup variable |
_SUBC_ | subgroup number of nonconformities |
_SUBN_ | subgroup sample size |
_TESTS_ | tests for special causes signaled on c chart |
_UCLC_ | upper control limit for number of nonconformities |
_VAR_ | process specified in the CCHART statement |
In addition, the following variables, if specified, are included:
Notes:
For an example, see "Saving Control Limits" .
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