ULTAREAUNITALL (HV004) is a number assigned to each sample point to identify the ultimate area units used in the collection of data. This variable is usually the same as the cluster number [CLUSTERNOALL (HV001)], but it may be a sequentially-numbered variable for samples with a more complicated sampling structure.
ULTAREAUNITALL can be used to account for the effects of sampling design clustering on variance estimates and standard errors.
Identifiers Variables -- TOPICS
Imputation and derivation
ULTAREAUNITALL (HV004) is a 4-digit variable.