Answering Unanswered Questions through Semantic Reformulations in Spoken QA

Pedro Faustini, Zhiyu Chen, Besnik Fetahu, Oleg Rokhlenko, Shervin Malmasi


Abstract
Spoken Question Answering (QA) is a key feature of voice assistants, usually backed by multiple QA systems. Users ask questions via spontaneous speech that can contain disfluencies, errors, and informal syntax or phrasing. This is a major challenge in QA, causing unanswered questions or irrelevant answers, leading to bad user experiences. We analyze failed QA requests to identify core challenges: lexical gaps, proposition types, complex syntactic structure, and high specificity. We propose a Semantic Question Reformulation (SURF) model offering three linguistically-grounded operations (repair, syntactic reshaping, generalization) to rewrite questions to facilitate answering. Offline evaluation on 1M unanswered questions from a leading voice assistant shows that SURF significantly improves answer rates: up to 24% of previously unanswered questions obtain relevant answers (75%). Live deployment shows positive impact for millions of customers with unanswered questions; explicit relevance feedback shows high user satisfaction.
Anthology ID:
2023.acl-industry.70
Volume:
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 5: Industry Track)
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Sunayana Sitaram, Beata Beigman Klebanov, Jason D Williams
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
729–743
Language:
URL:
https://aclanthology.org/2023.acl-industry.70
DOI:
10.18653/v1/2023.acl-industry.70
Bibkey:
Cite (ACL):
Pedro Faustini, Zhiyu Chen, Besnik Fetahu, Oleg Rokhlenko, and Shervin Malmasi. 2023. Answering Unanswered Questions through Semantic Reformulations in Spoken QA. In Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 5: Industry Track), pages 729–743, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
Answering Unanswered Questions through Semantic Reformulations in Spoken QA (Faustini et al., ACL 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.acl-industry.70.pdf