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Learning Attributes and Relations
Ontology Learning from Text
Philipp Cimiano, Chapter 7
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7.1 Common Approaches
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Collocations
Syntactic Dependencies
Lexico-syntactic patterns (Hearst, 1992)
Road Map:
– Learning Attributes
– Learning the Appropriate Generalization Level for
Relations
– Learning Qualia Structures
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7.2 Learning Attributes
• Attribute = a relation with a datatype as range
• Learn name, domain, and range
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7.3 Learning Relations from Corpora
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Based on verbal expressions
Generalization of argument wrt taxonomy
Statistical measures for generalization
Approach:
– Extract verb frames
– Generalize verb frames – statistical measures:
• Conditional probability
• Pointwise mutual information
• X2 measure
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7.4 Learning Qualia Structures from
the Web
• Aristotle’s four basic factors or causes:
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the material cause – made of
the agentive cause – source of creation or change
the formal cause – form or type
the final cause – purpose, intention, or aim
• Pustejovsky (1991): four roles in qualia structure:
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constitutive – parts or components
agentive – verb, action brings into existence
formal – type information
telic – purpose or function
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7.5 Related Work
• Madche and Staab (2000) – generalized association
rules algorithm
• Kavalec and Svátek (2005) – label verbs as “above
expectations”
• Gamallo et al. (2002) – map syntactic dependencies to
semantic relations
• Ciaramita et al. (2005) – learn conceptual relations
from the GENIA corpus
• Heyer et al. (2001) – derive conceptual relations from
corpus collocations and heuristics
• Ogata and Collier ( 2004) – relations based on patterns
similar to Hearst + reasoning
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more Related Work
• Yamaguchi (2001) – WordNet pruning + Schuetze’s
word space method with word 4-grams
• Buitelaar et al. (2004) – mapping with slots for domain
and range, manual inspection
• Pesio and Almuhareb ( 2005) – six categories of
attributes, train a classifier
• Yamada and Baldwin (2004) – learn telic and agentive
relations from corpora, dependencies
• Claveau et al. (2003) – Inductive Logic Programming to
find qualia verbs
• Pustejovsky et al. (1993) – acquire relations from
corpora, statistics and theoretical lexicon principles
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7.6 Conclusion and Open Issues
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Use adjectives and WordNot to learn attributes
Statistical learning of slots for verbs
Learning qualia structures
Learning from noun phrases?
Meaning of qualia roles?
Distinguish word senses?
Gold standard for qualia structures?
Calculus to reason on partial results?
Constrain according to linguistic principles?
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