For the foreseeable future, natural language access to databases and other information systems will require the exchange of written messages between the system and user. Such written/interactive dialogue is unique, having the qualities of both written text and spoken discourse yet, also, differing significantly from both. In the present study, we used "Wizard of Oz" techniques to elicit written/interactive dialogue for information retrieval purposes. Our objectives in doing this were (a) to assess the general nature and prevalence of linguistic and dialogue phenomena within the written/interactive register and (b) to determine the impact of user interface shortcuts, such as precanned messages and patterned output, on both the complexity of written/interactive dialogue and general measures of user satisfaction. Our findings indicate that written/interactive dialogue for information retrieval would be very feasible. In spite of slow system response times, subjective reactions from the users were positive, the size of the lexicon used in the dialogues was small, the dialogues decomposed readily into hierarchical structures, and the number and distribution of anaphors were also rather reasonable. Two independent variables were also manipulated: (a) the degree of prefamiliarization given to participants about the base of travel information they would be accessing (i.e., the primer variable) and (b) the degree of constraint on the Wizard's ability to formulate natural language responses to the user (i.e., the natural language output variable). Failure to provide either a primer or a realistic, human natural language output made the dialogues more complex in a number of different ways.

In this study we map out a way to build event representations incrementally, using information which may be widely distributed across a discourse. An enhanced Discourse Representation (Kamp, 1981) provides the vehicle both for carrying open event roles through the discourse until they can be instantiated by NPs, and for resolving the reference of these otherwise problematic NPs by binding them to the event roles.

This empirical study attempts to find answers to the question of how a natural language (henceforth NL) system could resolve attachment of prepositional phrases (henceforth PPs) by examining naturally occurring PP attachments in typed dialogue. Examination includes testing predictive powers of existing attachment theories against the data. The result of this effort will be an algorithm for interpreting PP attachment.