def normalized_mutual_info_score(self, reference_clusters):
        """
        Calculates the normalized mutual information w.r.t. the reference clusters (explicit evaluation)

        :param reference_clusters: Clusters that are to be used as reference
        :return: The resulting normalized mutual information score.
        """
        return normalized_mutual_info_score(self.get_labels(self), self.get_labels(reference_clusters))