tailieunhanh - Báo cáo khoa học: "Intonational Boundaries, Speech Repairs and Discourse Markers: Modeling Spoken Dialog"

To understand a speaker's turn of a conversation, one needs to segment it into intonational phrases, clean up any speech repairs that might have occurred, and identify discourse markers. In this paper, we argue that these problems must be resolved together, and that they must be resolved early in the processing stream. We put forward a statistical language model that resolves these problems, does POS tagging, and can be used as the language model of a speech recognizer. We find that by accounting for the interactions between these tasks that the performance on each task improves, as does POS. | Intonational Boundaries Speech Repairs and Discourse Markers Modeling Spoken Dialog Peter A. Heeman and James F. Allen Department of Computer Science University of Rochester Rochester NY 14627 USA heeman james @cs. Abstract To understand a speaker s turn of a conversation one needs to segment it into in-tonational phrases clean up any speech repairs that might have occurred and identify discourse markers. In this paper we argue that these problems must be resolved together and that they must be resolved early in the processing stream. We put forward a statistical language model that resolves these problems does POS tagging and can be used as the language model of a speech recognizer. We find that by accounting for the interactions between these tasks that the performance on each task improves as does POS tagging and perplexity. 1 Introduction Interactive spoken dialog provides many new challenges for natural language understanding systems. One of the most critical challenges is simply determining the speaker s intended utterances both segmenting the speaker s turn into utterances and determining the intended words in each utterance. Since there is no well-agreed to definition of what an utterance is we instead focus on intonational phrases Silverman et al. 1992 which end with an acoustically signaled boundary tone. Even assuming perfect word recognition the problem of determining the intended words is complicated due to the occurrence of speech repairs which occur where the speaker goes back and changes or repeats something she just said. The words that are replaced or repeated are no longer part of the intended utterance and so need to be identified. The following example from the Trains corpus Heeman and Allen 1995 gives an example of a speech repair with the words that the speaker intends to be replaced marked by reparandum the words that are the intended replacement marked as alteration and the cue phrases and filled pauses that tend to occur in .