Experiences from Combining Dialogue System Development with Information Extraction Techniques

Traditional Q&A systems are efficient at interpretation of single questions and extraction of the corresponding answer from unstructured texts, but cannot handle many of the interaction features that make dialogue systems so efficient for information access. Dialogue systems, on the other hand, can handle connected dialogues, but are normally developed to access structured data, often stored in databases. The challenge is therefore to combine these areas of language technology research and develop dialogue systems that can access information from unstructured text documents. A first step towards this goal is to use information extraction techniques that pull out relevant information from textual documents to compile unstructured information to a database. This might sound as a straightforward endeavour, but in practice, it involves a number of research issues, such as, handling different ontological perspectives, dealing with information gaps, inference both inside the dialogue and in the interpretation of source documents, etc. We have addressed this combined research issue of utilising information extraction techniques to automatically create structured databases from unstructured documents to be accessed by dialogue systems. A system, BirdQuest, has been developed based on a bird encyclopaedia from which information was extracted and transformed to a relational database. In the paper we present the system architecture, its components, and evaluations from the perspectives of users of the system and the development of a dialogue system that access a database created automatically utilising information extraction.