PCHART Statement: ANOM Procedure

You can read count data from a DATA= data set specified in the PROC ANOM statement. Each response specified in the PCHART statement must be a SAS variable in the DATA= data set. This variable provides counts for group samples indexed by the values of the group-variable. The group-variable, which is specified in the PCHART statement, must also be a SAS variable in the DATA= data set. Each observation in a DATA= data set must contain a count for each response and a value for the group-variable. The data set must contain one observation for each group. Note that you can specify the DATAUNIT= option in the PCHART statement to read proportions or percentages instead of counts. Other variables that can be read from a DATA= data set include

When you use a DATA= data set with the PCHART statement, the GROUPN= option (which specifies the group sample size) is required.

For an example of a DATA= data set, see Creating ANOM Charts for Proportions from Group Counts.

You can read preestablished decision limits (or parameters from which the decision limits can be calculated) from a LIMITS= data set specified in the PROC ANOM statement. For example, the following statements read decision limit information from the data set Conlims:

proc anom data=Info limits=Conlims;
   pchart Rejects*Batch / groupn= 100;
run;

The LIMITS= data set can be an OUTLIMITS= data set that was created in a previous run of the ANOM procedure. Such data sets always contain the variables required for a LIMITS= data set. The LIMITS= data set can also be created directly using a DATA step. When you create a LIMITS= data set, you must provide one of the following:

In addition, note the following:

You can read group summary statistics from a SUMMARY= data set specified in the PROC ANOM statement. This enables you to reuse OUTSUMMARY= data sets that have been created in previous runs of the ANOM procedure or to create your own SUMMARY= data set.

A SUMMARY= data set used with the PCHART statement must contain the following:

The names of the proportion sample size variables must be the response name concatenated with the special suffix characters P and N, respectively.

For example, consider the following statements:

proc anom summary=Summary;
   pchart (Rework Rejected)*Batch / groupn=50;
run;

The data set Summary must include the variables Batch, ReworkP, ReworkN, RejetedP, and RejetedN.

Note that if you specify a response name that contains 32 characters, the names of the summary variables must be formed from the first 16 characters and the last 15 characters of the response name, suffixed with the appropriate character.

Other variables that can be read from a SUMMARY= data set include

For an example of a SUMMARY= data set, see Creating ANOM Charts for Proportions from Group Summary Data.

You can read summary statistics and decision limits from a TABLE= data set specified in the PROC ANOM statement. This enables you to reuse an OUTTABLE= data set created in a previous run of the ANOM procedure. Because the ANOM procedure simply displays the information read from a TABLE= data set, you can use TABLE= data sets to create specialized ANOM charts.

The following table lists the variables required in a TABLE= data set used with the PCHART statement:

Other variables that can be read from a TABLE= data set include

For an example of a TABLE= data set, see Saving Decision Limits.