Conversation and its Structure

26.2 Dialog acts and corpora

1. What is a dialogue act?
   A tag representing the interactive function of an utterance, combining speech acts and grounding; tagsets depend on the participants and on whether the dialogue is task-based.
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, p. 595
2. Give example dialogue acts from a meeting-scheduling tagset (Verbmobil).

   SUGGEST	from thirteenth through seventeenth June
   ACCEPT	Saturday sounds fine
   REJECT	No Friday I’m booked all day
   CLARIFY	do you mean Tuesday the 23rd?
   DELIBERATE	Let me check my calendar here
   GIVE REASON	Because I have meetings all afternoon

   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, pp. 595–596
3. How do dialogue acts in a restaurant system (HIS) carry content?
   Each act has slot–value arguments: “I’d like an Italian somewhere near the museum” = inform(food=Italian, near=museum); “Is it reasonably priced?” = confirm(pricerange=moderate); “What is the phone number?” = request(phone).
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, pp. 596–597
4. In the HIS tagset, what is the difference between CONFIRM, CONFREQ, NEGATE and DENY?
   CONFIRM explicitly confirms values; CONFREQ (system only) implicitly confirms some values while requesting another; NEGATE (user only) negates and gives the corrected value; DENY (user only) just denies that a = x.
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, p. 596
5. What two kinds of functions does DAMSL tag for each utterance?
   Forward-looking functions (speech-act functions like STATEMENT, INFO-REQUEST, ACTION-DIRECTIVE, OFFER, COMMIT) and backward-looking functions relating to the interlocutor’s previous utterance (agreement, answering, grounding).
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, p. 596
6. Give DAMSL’s forward-looking functions.
   STATEMENT; INFO-REQUEST; CHECK (confirming information); influence on addressee (Bach’s directives): OPEN-OPTION (weak suggestion), ACTION-DIRECTIVE (actual command); influence on speaker (commissives): OFFER, COMMIT; conventional: OPENING, CLOSING, THANKING.
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, p. 597
7. Give DAMSL’s backward-looking functions.
   Agreement (ACCEPT, ACCEPT-PART, MAYBE, REJECT-PART, REJECT, HOLD, often via subdialogue); ANSWER; understanding: SIGNAL-NON-UNDERSTANDING, SIGNAL-UNDERSTANDING via ACK (continuer or assessment), REPEAT-REPHRASE, or COMPLETION.
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, p. 597
8. Give DAMSL labels for: A: “And, what day in May did you want to travel?” C: “OK uh I need to be there for a meeting that’s from the 12th to the 15th.” A: “And you’re flying into what city?” C: “Seattle.”

   A	[info-req, ack]
   C	[assert, answer]
   A	[info-req, ack]
   C	[assert, answer]

   The “And” at the start of each question grounds the previous answer (ack).
   • Jurafsky & Martin, Speech and Language Processing, 3rd ed. draft, ch. 26, §26.2, p. 598