1. A method of constructing a domain-specific sentiment classifier for classifying sentiment expressed by documents in a specified domain, comprising: scoring sentiments expressed by a plurality of domain-specific documents responsive to a domain-independent sentiment lexicon; identifying a set of high-sentiment documents responsive to the scoring; creating a domain-specific sentiment lexicon based at least in part on the set of high-sentiment documents; generating the domain-specific sentiment classifier responsive to the domain-specific sentiment lexicon; and storing the domain-specific sentiment classifier.
9. The method of claim 1 , wherein generating the domain-specific sentiment classifier responsive to the domain-specific sentiment lexicon comprises: building a model having n-grams of the domain-specific sentiment lexicon as features; and training the model on a training corpus having domain-specific documents having manually-labeled sentiment scores.