<p>The work in this thesis addresses design and development of multimodal dialogue recommender systems for the home context-of-use. In the design part, two investigations on multimodal recommendation dialogue interaction in the home context are reported on. The first study gives implications for the design of dialogue system interaction including personalization and a three-entity multimodal interaction model accommodating dialogue feedback in order to make the interaction more efficient and successful. In the second study a dialogue corpus of movie recommendation dialogues is collected and analyzed, providing a characterization of such dialogues. We identify three initiative types that need to be addressed in a recommender dialogue system implementation: system-driven preference requests, userdriven information requests, and preference volunteering. Through the process of dialogue distilling, a dialogue control strategy covering system-driven preference requests from the corpus is arrived at.</p><p>In the development part, an application-driven development process is adopted where reusable generic components evolve through the iterative and incremental refinement of dialogue systems. The Phase Graph Processor (PGP) design pattern is one such evolved component suggesting a phase-based control of dialogue systems. PGP is a generic and flexible micro architecture accommodating frequent change of requirements inherent of agile, evolutionary system development. As PGP has been used in a series of previous information-providing dialogue system projects, a standard phase graph has been established that covers the second initiative type; user-driven information requests. The phase graph is incrementally refined in order to provide user preference modeling, thus addressing the third initiative type, and multimodality as indicated by the user studies. In the iterative development of the multimodal recommender dialogue system MADFILM the phase graph is coupled with the dialogue control strategy in order to cater for the seamless integration of the three initiative types.</p> / Report code: LiU-TEK-LIC-2004:08.

In this thesis, the design and use of ontologies as domain knowledge sources in information-providing dialogue systems are investigated. The research is divided into two parts, theoretical investigations that have resulted in a requirements specifications on the design of ontologies to be used in information-providing dialogue systems, and empirical work on the development of a framework for use of ontologies in information-providing dialogue systems. The framework includes three models: A model for ontology-based semantic analysis of questions. A model for ontology-based dialogue management, specifically focus management and clarifications. A model for ontology-based domain knowledge management, specifically transformation of user requests to system oriented concepts used for information retrieval. In this thesis, it is shown that using ontologies to represent and reason on domain knowledge in dialogue systems has several advantages. A deeper semantic analysis is possible in several modules and a more natural and efficient dialogue can be achieved. Another important aspect is that it facilitates portability; to be able to reuse adapt the dialogue system to new tasks and domains, since the domain-specific knowledge is separated form generic features in the dialogue system architecture. Other advantages are that it reduces the complexity of linguistic produced in various domains.

The work in this thesis addresses design and development of multimodal dialogue recommender systems for the home context-of-use. In the design part, two investigations on multimodal recommendation dialogue interaction in the home context are reported on. The first study gives implications for the design of dialogue system interaction including personalization and a three-entity multimodal interaction model accommodating dialogue feedback in order to make the interaction more efficient and successful. In the second study a dialogue corpus of movie recommendation dialogues is collected and analyzed, providing a characterization of such dialogues. We identify three initiative types that need to be addressed in a recommender dialogue system implementation: system-driven preference requests, userdriven information requests, and preference volunteering. Through the process of dialogue distilling, a dialogue control strategy covering system-driven preference requests from the corpus is arrived at. In the development part, an application-driven development process is adopted where reusable generic components evolve through the iterative and incremental refinement of dialogue systems. The Phase Graph Processor (PGP) design pattern is one such evolved component suggesting a phase-based control of dialogue systems. PGP is a generic and flexible micro architecture accommodating frequent change of requirements inherent of agile, evolutionary system development. As PGP has been used in a series of previous information-providing dialogue system projects, a standard phase graph has been established that covers the second initiative type; user-driven information requests. The phase graph is incrementally refined in order to provide user preference modeling, thus addressing the third initiative type, and multimodality as indicated by the user studies. In the iterative development of the multimodal recommender dialogue system MADFILM the phase graph is coupled with the dialogue control strategy in order to cater for the seamless integration of the three initiative types.