1. An information processing device comprising: a cluster information acquisition unit which acquires information indicating a cluster which is a set of records in an anonymized state in which at least a portion of attribute values of set-valued attributes, which can include one value or a plurality of values included in the records, is removed from the cluster which is a set of records including an attribute value so that the cluster satisfies a predetermined anonymity; and a set-valued attribute refinement unit which discloses at least a portion of attribute values from among removed attribute values of the set-valued attributes of records included in the cluster acquired by the cluster acquisition, and divides the cluster into clusters which satisfy the predetermined anonymity based on the disclosed attribute values.