A system and method of multi-pass recognition for conversational spoken dialogue systems includes two speech recognizers: a first recognizer that implements, for example, a statistical language model (SLM) and a second recognizer that implements, for example, a grammar-based model. A word-spotting speech recognizer may be included, as may confidence estimators for each speech recognizer. The system and method provide a multi-pass approach to speech recognition, which reevaluates speech inputs to improve recognition where confidence scores returned from confidence estimators are low.
