Results Clear distinction between two question intonations: perception and understanding level Three distinct prototypes for different interpretations Future work Will be implemented and tested in Higgins to evaluate user responses and dialogue efficiency Corpus study of human-human dialog Multi-syllable, multi-word, accent II Back-channels (hmm, eh) Multimodal synthesis (max 48) The Effects of Prosodic Features on the Interpretation of Clarification Ellipses Jens Edlund, David House and Gabriel Skantze Abstract In this paper, the effects of prosodic features on the interpretation of elliptical clarification requests in dialogue are studied. An experiment is presented where subjects were asked to listen to short human-computer dialogue fragments in Swedish, where a synthetic voice was making an elliptical clarification after a user turn. The prosodic features of the synthetic voice were systematically varied, and the subjects were asked to judge what was actually intended by the computer. The results show that an early low F0 peak signals acceptance, that a late high peak is perceived as a request for clarification of what was said, and that a mid high peak is perceived as a request for clarification of the meaning of what was said. Setting Levels of understanding Allwood et al. (1992), Clark (1996) Ellipsis interpretation Errors and clarification in dialog Dialog not always error free Error detection often made using explicit or implicit spoken clarification/verification: User[…] on the right I see a red building. System (low conf.) Did you say ’A red building’? System (high conf.)A red building… ok, take a left […]? Traditionally: Clarification Ellipses User[…] on the right I see a red building. Systemred(?) Advantages: Level AcceptanceH accepts what S says UnderstandingH understands what S says PerceptionH hears what S says ContactH hears that S speaks Experiment 8 subjects judged the meaning of one-word elliptical clarification requests in dialogue context Task:Select paraphrase for elliptical system utterance Swedish System utterance: red, blue, yellow F 0 peak position: early, mid, late F 0 peak height: low, high Vowel duration: normal, long = 36 stimuli LUKAS diphone MBROLA synthesis LevelParaphrase Signal AcceptanceOk, red. Clarify UnderstandingDo you really mean red? Clarify PerceptionDid you say red? The Higgins spoken dialog system for pedestrian navigation No effects for: Subject Color Duration Prototypes: Accept: Early low peak Clarify Understanding: Mid high peak Clarify Perception: Late high peak The Problem Elliptical one-word clarification requests are potentially ambiguous Little syntax and structure Prosody more critical How do prosodic features affect the interpretation of these utterances? Constructed as full propositions Often perceived as tedious Clarifies entire user utterances Fast Focuses on problematic fragment Often used in human-human dialog Question intonation Swedish question intonation Raised top-line and widened F0 range on focal accent (Gårding, 1998) Delayed focal peak (House, 2003) German dialog Rodriguez & Schlangen (2004) Rising boundary tones to clarify acoustic problems (perception) Used less for reference resolution (understanding)