The FACTOR Procedure
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Overview
- Getting Started
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Syntax
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Details
Input Data Set Output Data Sets Confidence Intervals and the Salience of Factor Loadings Simplicity Functions for Rotations Missing Values Cautions Factor Scores Variable Weights and Variance Explained Heywood Cases and Other Anomalies about Communality Estimates Time Requirements Displayed Output ODS Table Names ODS Graphics
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Examples
- References
| BY Statement |
You can specify a BY statement with PROC FACTOR to obtain separate analyses on observations in groups that are defined by the BY variables. When a BY statement appears, the procedure expects the input data set to be sorted in order of the BY variables. If you specify more than one BY statement, only the last one specified is used.
If your input data set is not sorted in ascending order, use one of the following alternatives:
Sort the data by using the SORT procedure with a similar BY statement.
Specify the NOTSORTED or DESCENDING option in the BY statement for the FACTOR procedure. The NOTSORTED option does not mean that the data are unsorted but rather that the data are arranged in groups (according to values of the BY variables) and that these groups are not necessarily in alphabetical or increasing numeric order.
Create an index on the BY variables by using the DATASETS procedure (in Base SAS software).
If you specify the TARGET= option and the TARGET= data set does not contain any of the BY variables, then the entire TARGET= data set is used as a Procrustean target for each BY group in the DATA= data set.
If the TARGET= data set contains some but not all of the BY variables, or if some BY variables do not have the same type or length in the TARGET= data set as in the DATA= data set, then PROC FACTOR displays an error message and stops.
If all the BY variables appear in the TARGET= data set with the same type and length as in the DATA= data set, then each BY group in the TARGET= data set is used as a Procrustean target for the corresponding BY group in the DATA= data set. The BY groups in the TARGET= data set must be in the same order as in the DATA= data set. If you specify the NOTSORTED option in the BY statement, there must be identical BY groups in the same order in both data sets. If you do not specify the NOTSORTED option, some BY groups can appear in one data set but not in the other.
For more information about BY-group processing, see the discussion in SAS Language Reference: Concepts. For more information about the DATASETS procedure, see the discussion in the Base SAS Procedures Guide.