19. The system of claim 11 , wherein to form the topic cluster includes to: add to the topic cluster a set of words that is found in the data set and deemed to be most similar to the seed word; determine similarity weights of remaining words in the data set; and add to the topic cluster those remaining words whose similarity weights at least meets a weight threshold.
19. The system of claim 11 , wherein to form the topic cluster includes to: add to the topic cluster a set of words that is found in the data set and deemed to be most similar to the seed word; determine similarity weights of remaining words in the data set; and add to the topic cluster those remaining words whose similarity weights at least meets a weight threshold. 20. The system of claim 19 , wherein a similarity weight of a remaining word is determined based on a sum of similarities between the remaining word and existing words in the topic cluster.