Reversibility and Self-Monitoring
in Natural Language Generation

Günter Neumann* and Gertjan van Noord**

* Deutsches Forschungszentrum für Künstliche Intelligenz Saarbrücken
** Vakgroep Alfa-informatica Rijksuniversiteit Groningen

Abstract:

This paper shows how the use of reversible grammars may lead to efficient and flexible natural language parsing and generation systems.

In particular a mechanism is described which ensures that only non-ambiguous utterances are produced. This mechanism uses the parsing component to monitor the generation component. The relevant communication between the two components is performed using derivation trees. For this reason the proposed mechanism only makes sense for systems in which a single grammar is used for both parsing and generation.

Furthermore we define a variant of the monitoring strategy which can be used to paraphrase a given input sentence (for interactive disambiguation). In this case, the generation component is used to guide the parsing system. Again the proposed technique is possible only in the case of a single, reversible grammar.