CLUSTER Statement

The SURVEYMEANS Procedure

CLUSTER Statement

CLUSTER $\, | \,$ CLUSTERS variables ;

The CLUSTER statement names variables that identify the clusters in a clustered sample design. The combinations of categories of CLUSTER variables define the clusters in the sample. If there is a STRATA statement, clusters are nested within strata.

If your sample design has clustering at multiple stages, you should identify only the first-stage clusters, or primary sampling units (PSUs), in the CLUSTER statement. See the section "Primary Sampling Units (PSUs)" for more information.

The CLUSTER variables are one or more variables in the DATA= input data set. These variables can be either character or numeric. The formatted values of the CLUSTER variables determine the CLUSTER variable levels. Thus, you can use formats to group values into levels. Refer to the discussion of the FORMAT procedure in the SAS Procedures Guide and to the discussions of the FORMAT statement and SAS formats in SAS Language Reference: Dictionary.

You can use multiple CLUSTER statements to specify cluster variables. The procedure uses variables from all CLUSTER statements to create clusters.

Chapter Contents
Previous
Next
Top