A dialogue act represents the interactive function of a turn or sentence within a dialogue, combining the notions of speech act and grounding into a single representation. Dialogue systems use dialogue acts to label and interpret utterances, and different types of dialogue systems require labeling different kinds of dialogue acts.

Dialogue Act

Act of the hearer acknowledging that they understood the speaker; this is important in gelling the dialogue into a singular, flowing conversation

Carleton College

Intricate components of natural human conversation that must be considered when creating a dialogue system

1) Turn Structure

2) Speech Acts

3) Grounding

4) Dialogue Structure

5) Initiative

6) Implicature

Properties of Human Conversation

An on-going but a helpful book resource about NLP
https://web.stanford.edu/~jurafsky/slp3/

Speech and Language Processing (3rd ed. draft) 

Dialogue consists of two or more agents taking turns speaking. Dialogue systems must be able to detect when a user is done speaking and thus it is their turn to talk (called end pointing)

Turn Structure

Every utterance in a dialogue falls under a type of speech act. Knowing the speech act of an utterance is important in understanding the speaker's intention

Speech Acts

Grounding

Dialogues typically follow a dialogue structure that comes second nature to humans; some examples of dialogue structure are:

- Questions are followed by answers

- Greetings are met with a reciprocal greeting

- Compliments are followed with a down-player ("that's amazing!" -> "oh it's nothing") 

Dialogue Structure

Initiative is when a speaker takes control of a conversation; this typically means they guide the direction and topics of the conversation

Initiative

Implicature is the act of conveying more information in an utterance than what is directly said in their words

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