19. The method of claim 18 , wherein the post-hoc annotation machine learning model is configured to receive as input (i) the first input conversational turn, (ii) the first annotation, (iii) one or more conversational turns occurring before the first input conversational turn in the dialogue, and (iv) one or more conversational turns occurring after the first input conversational turn in the dialogue.
18. The method of claim 12 , wherein determining that the first annotation accurately characterized the first input conversational turn comprises: processing the first input conversational turn and the first annotation using a post-hoc annotation machine learning model that is configured to generate as output a quality score that represents a likelihood that the first annotation is an accurate characterization of the first input conversational turn; and determining that the quality score exceeds a threshold score.