8th International Conference on Spoken Language Processing

Jeju Island, Korea
October 4-8, 2004

Effects of Language Modeling on Speech-Driven Question Answering

Katsunobu Itou (1), Atsushi Fujii (2), Tomoyosi Akiba (3)

(1) Nagoya University, Japan
(2) University of Tsukuba, Japan
(3) Toyohashi University of Technology, Japan

We integrate automatic speech recognition (ASR) and question answering (QA) to realize a speech-driven QA system, and evaluate its performance. We adapt an N-gram language model to natural language questions, so that the input of our system can be recognized with a high accuracy. We target WH-questions which consist of the topic part and fixed phrase used to ask about something. We first produce a general N-gram model intended to recognize the topic and emphasize the counts of the N-grams that correspond to the fixed phrases. Given a transcription by the ASR engine, the QA engine extracts the answer candidates from target documents. We propose a passage retrieval method robust against recognition errors in the transcription. We use the QA test collection produced in NTCIR, which is a TREC-style evaluation workshop, and show the effectiveness of our method by means of experiments.

Full Paper

Bibliographic reference.  Itou, Katsunobu / Fujii, Atsushi / Akiba, Tomoyosi (2004): "Effects of language modeling on speech-driven question answering", In INTERSPEECH-2004, 1053-1056.