Answering definitional questions before they are asked

Most question answering systems narrow down their search space by issuing a boolean IR query on a keyword indexed corpus. This technique often proves futile for definitional questions, because they only contain one keyword or name. Thus, an IR search for only that term is likely to produce many spurious results; documents that contain mentions of the keyword, but not in a definitional context. An alternative approach is to glean the corpus in pre-processing for syntactic constructs in which entities are defined. In this thesis, I describe a regular expression language for detecting such constructs, with the help of a part-of-speech tagger and a named-entity recognizer. My system, named CoL. ForBIN, extracts entities and their definitions, and stores them in a database. This reduces the task of definitional question answering to a simple database lookup.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2004

Author dc:creator

• Fernandes, Aaron D. (Aaron David)

Advisor dc:contributor.advisor

• Boris Katz.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/33141

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/33141