Houjun Liu


A human Dialogue is a human to human interaction.


each contributino to a conversation is called a “turn”, which contains a sentence, multiple sentences, or a single word


  • when to take the floor
  • who takes the floor
  • what happens during interruptions?


barge-in is the property to allow the user to interrupt the system


deciding when a human has stopped talking, compute, etc.


each turn is actually an “action” performed by the user

  • constatives: committing the speaker to something being the case (answering, denying)
  • directives: ask the addressee to do something (advising, ordering)
  • com missives: commuting the speaker to future action (planning, voving)
  • acknowledgement: reflecting the speaker’s attitude for something (apologizing, greeting, etc.)

common ground

grounding is the problem of acknowledging and reflecting the state of interaction; such as the elevator lighting up when pressed.

acknowledgements and repeats is a way of grounding.

we need to make sure that the system acknowledges user interaction

adjacency pairs

  • question => answer
  • proposal => acceptance/rejection
  • complements => downplay

two-pair composition maybe interrupted or separated by a sub-dialogue

conversational initiative

Sometimes, such as during interviews, only one agent has initiative. This is not true most of the time during human-human interactions.

mixed initiative is hard to achieve, usually we make dialogue systems as passive environments—only user and system understanding.