Linguistic constraints for continuous speech recognition in goal-directed dialogue

The application of language models to continuous speech recognition, and the kinds of linguistic constraints important for improving speech recognition accuracy are discussed. First, the authors conducted an experiment to see how inter-phrase grammar contributes to the improvement of sentence speech recognition rates. The inter-phrase grammar was developed according to a dialogue database of an international conference secretarial service containing about a half-million words. It is confirmed that syntax is a very effective constraint for continuous speech recognition. Moreover, the predictive two-level LR parsing method is much better than the phrase lattice parsing method. The kinds of constraints that should, or can be, used to suppress each remaining error are discussed by referring to an example