Coherence maintenance in human-machine dialogue: indirect antecedents and ellipses

The paper discusses the use of dictionaries for resolving referential ambiguity in dialogue. We present a heuristic algorithm for detection of the indirect antecedents for dialogue phrases based on the use of a dictionary of prototypic scenarios associated with each headword, as well as of a thesaurus of the standard type. The conditions for filtration of the candidates for the antecedent are presented. The structure of the prototypic scenarios dictionary is discussed. We also present an algorithm for reconstruction of elliptical phrases of a special kind: short clarifications, in dialogue using a kind of combinatory dictionary with similar heuristic rules.