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CRYSTAL: Inducing a Conceptual Dictionary

Stephen Soderland·David Fisher·Jonathan Aseltine·Wendy Lehnert
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Abstract

One of the central knowledge sources of an information extraction system is a dictionary of linguistic patterns that can be used to identify the conceptual content of a text. This paper describes CRYSTAL, a system which automatically induces a dictionary of "concept-node definitions" sufficient to identify relevant information from a training corpus. Each of these concept-node definitions is generalized as far as possible without producing errors, so that a minimum number of dictionary entries cover the positive training instances. Because it tests the accuracy of each proposed definition, CRYSTAL can often surpass human intuitions in creating reliable extraction rules.

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Stephen Soderland, David Fisher, Jonathan Aseltine, Wendy Lehnert. 1995-05-09. CRYSTAL: Inducing a Conceptual Dictionary. https://arxiv.org/abs/cmp-lg/9505020

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