In order to maintain a modular design additional mechanisms are necessary to perform some monitoring and revision of the generator's output. Several authors argue for such additional mechanisms [Jameson and Wahlster1982, DeSmedt and Kempen1987, Joshi1987, Levelt1989, Neumann1991b]. For example, Levelt Levelt:89 pointed out that ``speakers monitor what they are saying and how they are saying it''. In particular he shows that a speaker is also able to note that what she is saying involves a potential ambiguity for the hearer and can handle this problem by means of self-monitoring. In this thesis we will present for the first time a computational model of monitoring based on reversible grammars.
The model introduced here is based on a strict integration of parsing and generation in the sense of
Before we give a detailed algorithmic characterization of the integrated approach we will consider current approaches that also take an integrated view of natural language processing.