2. The method of claim 1 , further comprising: reviewing, by the analyst, at least one sampling of word images in at least one word cluster; determining, based on judgment of the analyst, whether the sampled word images are the same word as the centroid for the word cluster and whether the sampled words have been correctly included in the word cluster; determining that a threshold number of the sampled word images have not been correctly included in the word cluster; and in response to determining that a threshold number of words have not been correctly included, marking the cluster as suspicious.
2. The method of claim 1 , further comprising: reviewing, by the analyst, at least one sampling of word images in at least one word cluster; determining, based on judgment of the analyst, whether the sampled word images are the same word as the centroid for the word cluster and whether the sampled words have been correctly included in the word cluster; determining that a threshold number of the sampled word images have not been correctly included in the word cluster; and in response to determining that a threshold number of words have not been correctly included, marking the cluster as suspicious. 3. The method of claim 2 , further comprising: determining that a threshold number of the sample word images have been correctly included in the cluster; and in response to determining that a threshold number of words have been correctly included in the cluster, maintaining the cluster.