ACTIVE Keyword (MULTIPLE CORRESPONDENCE command)
MODEIMPU. Impute missing values on a variable with the most frequent category (mode). When there are multiple modes, the smallest category indicator is used. This is the default.
EXTRACAT. Impute missing values on a variable with an extra category indicator. This implies that objects with a missing value are considered to belong to the same (extra) category.
Note: With active treatment of missing values, imputation is done before the analysis starts, and thus will affect the quantification and the solution.