Representation of the Data Documentation Initiative using

Semantic Web TechnologiesWorkshop on Semantic Statistics

12.09.2011 – 16.09.2011

Thomas Bosch(research associate, GESIS Leibniz Institute for the Social Sciences)

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Agenda

• Use Cases

• Take-aways and Discussion

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Publish and Link DDI Data and Metadata

Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. http://lod-cloud.net/

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Semantic Queries• What kinds of problems can be solved?• Queries on multiple, distributed and merged DDI instances• Formulation using DDI domain concepts

questionScheme

?question

?question

?question

contains

SELECT ?questionWHERE { questionScheme contains ?question. }

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Integration of Other Ontologies

• Domain ontologies' classes can relate to similar concepts of external ontologies• Reasoner may use additional semantic information

Other Ontologies

DDI Domain

Ontology

(Question) (Question)

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DDI Consistency Check

• Definition of 'consistency'• OWL reasoning techniques

• Class consistency• Global consistency

• Global consistency of DDI ontology Global consistency of DDI data model

Concept Hierarchy

text + html(superClassOf)

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Variable Concept

ConceptReference

Concept

SimilarConcept

Difference SimilarConceptReference

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Concept Hierarchy

Variable

Concept

hasConcept

subConceptOf

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DDI Elements‘ Comparability

CodeVariable

Grade_USA

Grade_Germany

1.0

A

hasCode

hasCode

subClassOf

subClassOf

subClassOf

subClassOf

• Necessary conditions (equality, inequality, similarity, …)

ReferencesOtherMaterial

Citation

DCElements

Title Creator

ExternalURLReference

RelatedToReference

Relationship

...

…

URN

...…

type

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ReferencesOtherMaterial

Citation

DCElements

Title Creator

ExternalURLReference

RelatedToReference

Relationship

...

…

URN

...…

type

Drawbacks:

• type• complex data model• no intuitive semantics• bibliographic citation

limits• ensure reusability?

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Semantic References

ReferencingPublication Publication

referencesPublication

Variable

subClassOf

publicationReferencedByX

Creator

ID

URLDateTitle

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Agenda

• Use Cases

• Take-aways and Discussion

http://ddiandsemanticweb.blogspot.com

LOD Cloud

Concept Hierarchies

Consistency

Comparability

Use Cases

SPARQL Queries

Ontology Integration

References