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dc.contributor.advisorPorter, Bruce, 1956-en
dc.creatorChaw, Shaw Yien
dc.date.accessioned2012-04-02T14:35:02Zen
dc.date.available2012-04-02T14:35:02Zen
dc.date.issued2009-12en
dc.date.submittedDecember 2009en
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2009-12-580en
dc.descriptiontexten
dc.description.abstractKnowledge base systems are brittle when the users of the knowledge base are unfamiliar with its content and structure. Querying a knowledge base requires users to state their questions in precise and complete formal representations that relate the facts in the question with relevant terms and relations in the underlying knowledge base. This requirement places a heavy burden on the users to become deeply familiar with the contents of the knowledge base and prevents novice users to effectively using the knowledge base for problem solving. As a result, the utility of knowledge base systems is often restricted to the developers themselves. The goal of this work is to help users, who may possess little domain expertise, to use unfamiliar knowledge bases for problem solving. Our thesis is that the difficulty in using unfamiliar knowledge bases can be addressed by an approach that funnels natural questions, expressed in English, into formal representations appropriate for automated reasoning. The approach uses a simplified English controlled language, a domain-neutral ontology, a set of mechanisms to handle a handful of well known question types, and a software component, called the Question Mediator, to identify relevant information in the knowledge base for problem solving. With our approach, a knowledge base user can use a variety of unfamiliar knowledge bases by posing their questions with simplified English to retrieve relevant information in the knowledge base for problem solving. We studied the thesis in the context of a system called ASKME. We evaluated ASKME on the task of answering exam questions for college level biology, chemistry, and physics. The evaluation consists of successive experiments to test if ASKME can help novice users employ unfamiliar knowledge bases for problem solving. The initial experiment measures ASKME's level of performance under ideal conditions, where the knowledge base is built and used by the same knowledge engineers. Subsequent experiments measure ASKME's level of performance under increasingly realistic conditions. In the final experiment, we measure ASKME's level of performance under conditions where the knowledge base is independently built by subject matter experts and the users of the knowledge base are a group of novices who are unfamiliar with the knowledge base. Results from the evaluation show that ASKME works well on different knowledge bases and answers a broad range of questions that were posed by novice users in a variety of domains.en
dc.format.mimetypeapplication/pdfen
dc.language.isoengen
dc.subjectKnowledge basesen
dc.subjectQuestion answeringen
dc.subjectProblem solvingen
dc.subjectNatural language processingen
dc.subjectProject Haloen
dc.subjectQuestion Mediatoren
dc.subjectDomain neutral ontologiesen
dc.subjectComponent Libraryen
dc.subjectControlled languagesen
dc.subjectAP examsen
dc.subjectMachine readingen
dc.titleAddressing the brittleness of knowledge-based question-answeringen
dc.date.updated2012-04-02T14:35:15Zen
dc.identifier.slug2152/ETD-UT-2009-12-580en
dc.contributor.committeeMemberBarker, Kenneth J.en
dc.contributor.committeeMemberMooney, Raymonden
dc.contributor.committeeMemberNovak, Gordon S.en
dc.contributor.committeeMemberMarkman, Arten
dc.description.departmentComputer Sciencesen
dc.type.genrethesisen
thesis.degree.departmentComputer Sciencesen
thesis.degree.disciplineComputer Sciencesen
thesis.degree.grantorThe University of Texas at Austinen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen


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