Understanding spontaneous speech: the Phoenix system

The author describes the design of the Phoenix speech understanding system and reports on its current status. Phoenix is a system currently being developed at Carnegie Mellon University to understand spontaneous speech. The system has been implemented for an air travel information service (ATIS) task. In the ATIS task, novice users are asked to perform a task that requires getting information from the air travel database. Users compose the questions themselves, and are allowed to phrase the queries any way they choose. No explicit grammar or lexicon is given to the subject. This task presents several problems not found in real input. Not only is the speech not fluent, but the vocabulary and grammar are open. The results of the processing of both the speech and transcript data for subjects performing the task are reported.<<ETX>>