19. The computer-readable medium of claim 16 including providing an opinion data store that specifies sequences of parts of speech that may express an opinion, a probability that each sequence contains a word that may express an opinion, and a probability that each word expresses an opinion.
19. The computer-readable medium of claim 16 including providing an opinion data store that specifies sequences of parts of speech that may express an opinion, a probability that each sequence contains a word that may express an opinion, and a probability that each word expresses an opinion. 20. The computer-readable medium of claim 19 wherein the opinion data store is generated by identifying from training data sequences of parts of speech that may express an opinion, calculating from the training data a probability that each sequence contains a word that may express an opinion, and calculating from the training data a probability that each word expresses an opinion.