The phrase "Hello, how have you been? It has been quite some time since we last met!" is an example of a common conversational greeting. Such openings are a fundamental part of dialogue structure, initiating an interaction and typically expecting a reciprocal greeting in response.

Example of a Conversational Greeting

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") 

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

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

Grounding

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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