1. Explanation for the Semantic Web
Rakebul Hasan

2. Explanation in the Semantic Web
What’s been done (existing work)
What’s ahead (perspective)
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3. What is explanation and why do we need it?
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4. Tim Berners-Lee was born in London
http://www.academiawiki.com/
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5. Tim Berners-Lee was born in London
http://www.academiawiki.com/
London is in England
http://www.geolocationwiki.com/
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6. Tim Berners-Lee was born in London
http://www.academiawiki.com/
London is in England
http://www.geolocationwiki.com/
Computer Scientists are Scientists
http://www.vocabularywiki.com/
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7. Tim Berners-Lee was born in London
http://www.academiawiki.com/
London is in England
http://www.geolocationwiki.com/
Computer Scientists are Scientists
http://www.vocabularywiki.com/
Tim Berners-Lee is a Computer Scientist
http://www.academiawiki.com/
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8. Tim Berners-Lee was born in London
http://www.academiawiki.com/
London is in England
http://www.geolocationwiki.com/
Computer Scientists are Scientists
http://www.vocabularywiki.com/
Tim Berners-Lee is a Computer Scientist
http://www.academiawiki.com/
England is part of United Kingdom
http://www.geolocationwiki.com/
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9. TimBernersLee
Tim Berners-Lee was born in London
http://www.academiawiki.com/
birthPlace
rdf:type London is in England
London
http://www.geolocationwiki.com/
Scientist
Computer Scientists are Scientists
http://www.vocabularywiki.com/ rdfs:subClassOf
ComputerScientist
Tim Berners-Lee is a Computer Scientist
isPartOf http://www.academiawiki.com/
UnitedKingdom
England is part of United Kingdom
http://www.geolocationwiki.com/
isPartOf
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10. TimBernersLee
birthPlace
rdf:type
London
Scientist
rdfs:subClassOf
ComputerScientist
isPartOf
England UnitedKingdom
isPartOf
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11. TimBernersLee Scientist
rdf:type rdfs:subClassOf
birthPlace
ComputerScientist
London UnitedKingdom
isPartOf
isPartOf
England
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12. TimBernersLee Scientist
rdf:type rdfs:subClassOf
birthPlace
ComputerScientist
London UnitedKingdom
isPartOf
isPartOf
England
App
• Reasoning
• RDFS/OWL
• Rules
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13. TimBernersLee Scientist
rdf:type
rdf:type rdfs:subClassOf
birthPlace
ComputerScientist
isPartOf
London UnitedKingdom
isPartOf
isPartOf
England
App
• Reasoning
• RDFS/OWL
• Rules
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14. TimBernersLee Scientist
rdf:type
rdf:type rdfs:subClassOf
birthPlace
ComputerScientist
birthPlace birthPlace
isPartOf
London UnitedKingdom
isPartOf
isPartOf
England
App
• Reasoning
• RDFS/OWL
• Rules
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15. TimBernersLee Scientist
rdf:type
rdf:type rdfs:subClassOf
birthPlace
ComputerScientist
birthPlace birthPlace
isPartOf
London UnitedKingdom
isPartOf
isPartOf
England
Scientists born in United Kingdom? App
• Reasoning
Answer: Tim Berners-Lee • RDFS/OWL
• Rules
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16. Tim Berners-Lee is a Scientist
Tim Berners-Lee was born in United Kingdom
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17. Tim Berners-Lee is a Computer Scientist
http://www.academiawiki.com/
Computer Scientists are Scientists
http://www.vocabularywiki.com/
Tim Berners-Lee is a Scientist
Tim Berners-Lee was born in United Kingdom
Tim Berners-Lee was born in England
England is part of United Kingdom
http://www.geolocationwiki.com/
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18. Tim Berners-Lee is a Computer Scientist
http://www.academiawiki.com/
Computer Scientists are Scientists
http://www.vocabularywiki.com/
Tim Berners-Lee is a Scientist
Tim Berners-Lee was born in London
Tim Berners-Lee was born in United Kingdom http://www.academiawiki.com/
London is in England
Tim Berners-Lee was born in England http://www.geolocationwiki.com/
England is part of United Kingdom
http://www.geolocationwiki.com/
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19. “Oh, yeah?” button to support users in assessing the
reliability of information encountered on the Web
- Tim Berners-Lee
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20. What’s been done
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21. What is explained?
Who are the targets?
How explanations are presented?
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22. What is explained?
• Information manipulation steps
• Information manipulation operations
• Proof tree of derivations
• Provenance information such as How, When, Who,
Where
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23. Target
• Human users
• Natural language explanation
• Graphical explanation
• Software agents
• Machine readable descriptions
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24. How explanations are presented?
How explanations are represented for machines?
How human users interact with explanations?
Trust
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25. Presentation
WIQA [Bizer, 2007]
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26. Presentation
KiWi [Kotowski and Bry, 2010]
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27. Presentation
KiWi [Kotowski and Bry, 2010]
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28. Presentation
Explaining entailments in OWL ontologies [Horridgeet al., 2008]
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29. Presentation
Inference Web [McGuinnesset al. (a), 2003] [McGuinnesset al. (b), 2006] [McGuinnesset al. (c), 2008]
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30. Presentation
EASD/KOIOS [Forcheret al., 2010]
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31. Presentation
EASD/KOIOS [Forcheret al., 2010]
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32. Metadata representation
• Proof trees for answers
• Operations used to compute answers
• Different types of provenance information
• Models for how explanations should be presented to
human users
• Trust related information
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33. Metadata representation
• Proof Markup Language (PML) Ontology
• Proof interlingua
• Justifications: information manipulation steps and
operations
• Provenance information
• Trust information
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34. Metadata representation
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35. Metadata representation
Accountability In RDF (AIR) [Kagalet al., 2011]
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36. Metadata representation
• KOIOS
• KOIOS Process Language (KPL) for describing the
behavior of KOIOS problem solver
• The Mathematical Graph Language (MGL) for
transforming the process model to a graph based view.
• VGL for describing the visualization model
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37. Metadata representation
EXPL: WIQA describes its explanation trees (parts and
subparts of an explanation) using the Explanation
(EXPL) Vocabulary
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38. Interaction
• Navigation
• Follow-up
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39. Interaction
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40. Interaction
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41. Trust
• Inference Web
• PML Trust vocabulary
• Trust explanation
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42. Trust
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43. What’s ahead
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44. Infrastructure
• Accommodating common data publishing principle
• Publishing explanation metadata along with data
using linked data principles
• Addressing heterogeneous and distributed nature of the
Web promoting interoperability
• W3C PROV-DM data model as an interchange data
model
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45. Target
• Level of user expertise should be taken into account
while providing explanation
• User profiling
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46. What is explained?
• Semantic Web applications use distributed
interconnected data in their reasoning process
• Explaining network of data used in the reasoning
process, flow of information
• How explanations exposing problem solving methods
influence security and confidentiality?
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47. Metadata representation
• Blank nodes are not good
• Granularity
• Provenance
• Interoperability
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48. Metadata representation
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49. r4ta:Assertion prov:specializationOf
prov:Entity r4ta:DirectAssertion r4ta:antecedent
r4ta:InferredAssertion
prov:Trace
r4ta:Justification prov:ProvenanceContainer
prov:Plan prov:Account
r4ta:InferenceRule
prov:hadPlan
prov:traceTo
r4ta:inferredByRule
r4ta:justifies
prov:qualifiedTrace prov:Activity
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50. Presentation
• User expertise
• What’s useful and what’s overwhelming?
• Context-aware data consumption
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51. Presentation
Summarization
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52. Presentation
Summarization
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53. Interaction
• What kind of interactions are useful need to be
understood
• How to interact established trust?
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54. Trust
• How explanation influence trust in the Semantic Web?
• How to capture established trust and reason over it?
• Explaining trust itself
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55. Trust
“If someone trusts a large company such as IBM, and IBM
brands other companies as ethical, then the person will
trust those companies, too”
– Tim Berners-Lee, Weaving the Web
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56. geo:about_london
<geo:london><voc:isPartOf><geo:England>.
<geo:london><rdfs:label> “London”@en.
<geo:london><voc:population> “7825200”^^xsd:integer.
<geo:london><voc:lat> “51.50853”^^xsd:decimal.
<geo:london><voc:long> “-0.12574”^^xsd:decimal.
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57. geo:about_london
<geo:london><voc:isPartOf><geo:England>.
<geo:london><rdfs:label> “London”@en.
<geo:london><voc:population> “7825200”^^xsd:integer.
<geo:london><voc:lat> “51.50853”^^xsd:decimal.
<geo:london><voc:long> “-0.12574”^^xsd:decimal.
endorses
trust
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58. geo:about_london
<geo:london><voc:isPartOf><geo:England>.
•Explicit endorsements
<geo:london><rdfs:label> “London”@en. •Incoming links: owl:sameAs
<geo:london><voc:population> “7825200”^^xsd:integer.
<geo:london><voc:lat> “51.50853”^^xsd:decimal.
<geo:london><voc:long> “-0.12574”^^xsd:decimal.
endorses
trust
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59. geo:about_london
<geo:london><voc:isPartOf><geo:England>.
•Explicit endorsements
<geo:london><rdfs:label> “London”@en. •Incoming links: owl:sameAs
<geo:london><voc:population> “7825200”^^xsd:integer.
<geo:london><voc:lat> “51.50853”^^xsd:decimal.
<geo:london><voc:long> “-0.12574”^^xsd:decimal.
•Explanation of trust and
endorsement network
endorses
trust
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60. Please see the research report RR-7974 for the list of references:
http://hal.inria.fr/hal-00702277
Thank you
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