Learning Attributes and Relations Ontology Learning from Text Philipp Cimiano, Chapter 7 11/27/2012 Cimiano Chapter 7 - PL

7.1 Common Approaches Collocations Syntactic Dependencies Lexico-syntactic patterns (Hearst, 1992) Road Map: Learning Attributes Learning the Appropriate Generalization Level for Relations Learning Qualia Structures 11/27/2012 Cimiano Chapter 7 - PL

7.2 Learning Attributes Attribute = a relation with a datatype as range Learn name, domain, and range 11/27/2012 Cimiano Chapter 7 - PL

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7.3 Learning Relations from Corpora 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 11/27/2012 Cimiano Chapter 7 - PL

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7.4 Learning Qualia Structures from the Web Aristotle’s four basic factors or causes: 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: constitutive – parts or components agentive – verb, action brings into existence formal – type information telic – purpose or function 11/27/2012 Cimiano Chapter 7 - PL

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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 11/27/2012 Cimiano Chapter 7 - PL

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 11/27/2012 Cimiano Chapter 7 - PL

7.6 Conclusion and Open Issues 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? 11/27/2012 Cimiano Chapter 7 - PL