Lexical, Prosodic, and Syntactics Cues for Dialog Acts

Purpose Investigating the particular class of dialogue acts called backchannels (aka "acknowledgement tokens"). Those give feedback to the speaker. Continuers – an utterance indicating that the other speaker should go on speaking. incipient speakership agreements – marks the degree to which a user accepts the speakers opinion, statement, etc. yes-answers Assessments – ascriptive sentences: expression of a certain property ("good," "bad").

Questions Does it have any importance as cue- phrases for the structure? Does prosodic knowledge have any importance? Is there any difference in syntactic realization of certain dialog acts, compared to others?

Who Cares? Part of a project to "automate discourse structure for speech recognition and understanding tasks" Create models of speakers and dialog.

Materials and Methods -SWBD-DAMSL dialog tagset: * an adaptation of DAMSL tag-set * ~60 labels that could be combined in different dimensions. -7 CU-Boulder linguistics grad students labeling switchboard conversations of human-to-human interaction

Results 220 unique tags for 205,000 utterances, where each utterance received exactly one tag. Good agreement rate between labelers (84%), but too many tags for statistical analysis  everything was condensed into 42 final tags

On the lexical level, do words like "yeah" have any importance as cue-phrases for the structure?" Hirschberg & Litman: "now" and "well." Here: words with overlap meanings Jurafsky’s Findings: utterances may be ambiguous, BUT through the lexical form, we could find the word's true "identity."

"Yeah" Vs. "uh-huh": “Yeah" (and variations): ambiguous ("agreements" at 36%, at "incipient speaker" at 59%", and 86% at "yes- answers") "uh-huh" (with its variations): a "continuer" (45% vs. "yeah" at 27%).

Next Question: "Does prosodic knowledge have any importance in determining DA's meaning?" Hirschberg and Litman: intonational phrasing and pitch accent disambiguates cue phrases and help determine discourse structure. Jurafsky: agrees. –Runs experiment: Text transcription vs. complete speech:

MATERIALS AND METHODS: 44 random, but previously labeled conversations. Conversations were put in full context as well as fully transcribed AND the original labeling was also available. RESULTS: 98% agreement!

2% The shifts: 38% of the 2%: continuers  agreements 19% of the 2%: opinions  statements 15% of the 2% statements  opinions Etc.

Why the Shifts? –due to cascading changes (continuer  agreement, preceding statement = opinion). –Nature of labeling instruction: ambiguous cases were labeled as continuers –Identical lexical form: some speakers distinguished agreement from continuer based on prosody, while others used lexical form.

Take Home Message Continuers are, in most cases (vs. agreements): –shorter in duration –less intonationally marked –long pauses before speaking

3 rd Question:Is there any difference in syntactic realization of certain dialog acts, compared to others? Goodwin and Goodwin: Pro Term + Copula + (Intensifier) + Assessment Adjective Formula happens frequently, where: –pro term mostly equals: "that" –intensifiers are rare, and are usually "really," and "pretty" –assessment adjective has small range of adjectives: great, good, nice, wonderful, etc.

Syntactic Conclusion "micro-syntax" – restricted grammatical production than would have thought. That is, certain dialog acts have their own syntactic patterning.