Combining Ontology Mapping Methods Using Bayesian Networks Ontology Alignment Evaluation Initiative

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Combining Ontology Mapping Methods Using Bayesian
NetworksOntology Alignment Evaluation Initiative
2006 - 'Conference' Track

• Ondrej váb
• Vojtech Svátek

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Overview

• Ontology Mapping
• Combining Ontology Mapping Methods
• Using Bayesian Networks
• String distance metrics
• Mapping patterns
• OAEI
• Our track conference domain
• Evaluation

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Ontology Mapping
Ontology Mapping discovering of Semantic
correspondencies (equivalence, subsumption)
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Classification of ontology mapping techniques
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Modelling of interdependencies (1)

• Using Bayesian Networks
• String distance metrics from SecondString library
  (mapping methods)
• Training data, pairs of concepts from ontologies
  ekaw.owl a confOf.owl from OntoFarm collection
• 798 pairs
• Bayesian network
• nodes mapping justification by each mapping
  method
• Classification node align (true, false)

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Modelling of interdependencies (2)

• Two tested Bayesian Networks (two corresponding
  classifiers)
• Naive Bayesian Structure
• Probability distributions learned from data
• Learned Bayesian Structure
• Learned both CPT and structure

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Evaluation of models

• One-leave-out method (798x)
• Evaluation precision, recall
• Precision more important than recall
• 32 (precision weight 0,6), 41 (0,8)
• C Pa Rb, kde a, b jsou váhy
• higher C, better classifier

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73 precision, 60 recall, 88 accuracy
at 80 threshold
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84 precision, 53 recall, 89 accuracy at
60 threshold
Align ci. CharJaccard, Monge-Elkan, Levenshtein
TFIDF, SmithWaterman, Jaccard, Jaro, SLIM
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Evaluation (c Pa Rb)
BN 2
Naive bayes
Jaccard
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Mapping patterns (1)

• Capturing structures using mapping patterns
• Mapping pattern between ontologies

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Mapping patterns (2)
Mapping pattern
Part of Bayesian Network
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Conclusions Future works

• Combination of string-based methods is not
  promising
• Implementation of low-level string based
  justifications of mapping suffix, prefix,
  identical names
• Capturing context Employ methods working with
  structures of ontologies (graph-based), mapping
  patterns
• Not only equivalence relations, but also
  discovery subsumption relations using
  linguistic sources, like WordNet

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Ontology Alignment Evaluation Initiative 2006 -
'Conference' Track
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OAEI 2006 at ISWC06

• Evaluation initiative in Ontology matching
• Since 2004
• In 2006 OAEI workshop at Ontology matching
  workshop, ISWC
• Four tracks (six data sets)
• Benchmark (biblio),
• Expressive ontologies anatomy (2 ontologies 10k
  classes), jobs (jobs and jobs seekers, real world
  case)
• Directory (web sites directory) 4 thousand
  elementary test, Food data set SKOS thesaurus
  about food with other food ontologies

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Conference track

• Coordinated by UEP
• Free exploration by participants within 10
  ontologies
• Domain conference organisation
• No a priori reference alignment
• Participants 6 research groups

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Ontologies in track
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Participants (1)

• Combination of methods lexicographic and
  contextual
• ISLab
• 11 matching approach
• Linguistic technique - thesaurus of terms and
  weighted terminological relationships is
  exploited
• Contextual technique - semantic relation in an
  ontology
• RiMOM
• Ontology alignment defined as a directional one
• Matchers Name-based (also NLP methods),
  Instance-based, Description-based, Taxonomy
  context-based, Constraints-based
• CtxMatch
• DL formulas
• Not only eq., also subsumption, disjointness,
  intersection

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Participants (2)

• COMA
• Extension of COMA
• Automs
• Lexical matching method, LSI, structural matching
  algorithm
• Falcon
• elementary matchers string-based, graph-based

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Evaluation (1)

• Personal judgement of organisers
• interesting individual correspondences (inverse
  compound names, eg. PC_Member Member_PC),
  synonyms
• Mapping errors subsumption, inversion role,
  siblings, lexical confusion
• Mapping between relation and class, eg.
  has_an_email and E-mail

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Evaluation (2)
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Evaluation (3)

• Subsumption error
• Author,Paper_Author
• Conference_Trip, Conference_part
• Inversion role error
• abstract_of_paper,reviewerOfPaper error
• Siblings
• ProgramCommittee,Technical_commitee
• Lexical confusion error
• program,Program_chair
• Relation Class mapping
• has_enddate,Date
• hasTitle,Title hasSurname,Surname

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Evaluation (4)
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Summary

• How to evaluate this track?
• Interesting mappings
• Recall?