The HWIM speech understanding system

HWIM, the speech understanding system developed at BBN as part of the recent five-year ARPA Speech Understanding Research Project, is designed to "understand" naturally spoken utterances relevant to a task domain of travel budget management. Its vocabulary is over 1000 words, and its grammar permits a relatively habitable subset of natural English. HWIM contains sources of knowledge at the levels of acoustic-phonetics, phonology, vocabulary, syntax, semantics, factual knowledge, and discourse. This paper describes the system as a whole and presents its performance results at the end of the project.