IMPJOINT Statement

  • IMPJOINT <variables>;

The IMPJOINT statement specifies the names of variables that are to be imputed jointly for the fully efficient fractional imputation (FEFI) method. If you do not use the IMPJOINT statement, then all the variables that you specify in the VAR statement are imputed jointly. You can use multiple IMPJOINT statements. The levels of the variables in the IMPJOINT statement describe a nonparametric imputation model for the expectation maximization (EM) step for the fractional imputation.

If you use the following IMPJOINT statements, then the variables y1, y2, and y3 are imputed jointly, and the variables y4 and y5 are imputed jointly:

IMPJOINT y1 y2 y3;

Analysis variables, which you specify in the VAR statement, can appear in only one IMPJOINT statement. However, auxiliary variables that you do not specify in the VAR statement can be specified in multiple IMPJOINT statements.

If you do not specify any variable names in the IMPJOINT statement, then every variable in the VAR statement is imputed marginally.

The IMPJOINT statement is ignored when you specify the METHOD=HOTDECK option in the PROC SURVEYIMPUTE statement.