open data masterclass - europeana and lod

Europeana and Linked Open Data

Antoine Isaac, Europeana

Open Data Masterclass, KB

9 October 2012

Building a search engine on top of metadata is difficultTraditional metadata quality problems: correctness, coverage

Especially when data is so heterogeneous100s of formats, multilingual data

We currently use a simple flat interoperability format (ESE)

Making metadata work for Europeana

More semantics-enabled services

Enhance access by semanticsQuery expansion, clustering of results

Exploiting various relations: "located in", “more specific concept"…

Goal: to make richer data and services available to us and others

Semantics are already there, in original metadataThesauri, classifications…

ESE loses information

Building a "semantic layer” context

Linked Data principles

1. Use URIs as names for things

2. Use HTTP URIs so that people can look up those names

3. When someone looks up a URI, provide useful information using standards (RDF, SPARQL)

4. Include links to other URIs, so that they can discover more things

Tim Berners-Lee http://linkeddata.org/

Example

http://data.europeana.eu/proxy/europeana/92037/25F9104787668C4B5148BE8E5AB8DBEF5BE5FE03

Leading to HTML page for humans

Leading to data for software agents

Also contextual resources

Contextual resources lead to data too

Matches interest for linked data in libraries, archives and museums

• Library Linked Data W3C Community Grouphttp://www.w3.org/2005/Incubator/lld/XGR-lld/

• LOD-LAM communityhttp://lod-lam.net

• IFLA Semantic Web grouphttp://www.ifla.org/en/swsig

LLD - General benefits of linked data

• ShareableGlobally unique resolvable identifiers – URI

• Extensible"Open world" - no description is complete, anybody can add descriptive

information about the same thingAnnotations, enrichments, etc.

• Standard protocols/techniques vs. domain-specific onesHTTP, RDF, REST

Etc.

http://www.w3.org/2005/Incubator/lld/XGR-lld/

Available Linked Library Data

http://www.w3.org/2005/Incubator/lld/XGR-lld-vocabdataset/

Available Library Linked Data

• Element sets/schemas/ontologiesSKOS, Dublin Core, OAI-ORE…

• Value vocabularies/thesauri/authority listsLCSH, VIAF…

• DatasetsBritish Library, Chronicling America…

Europeana and Linked Data

Provide trusted, reference data for cultural objects

Promote the use of the technology

Promoting the exchange of data in the community and with third parties: Open (meta)data!

http://vimeo.com/36752317

Europeana and Linked Data

Some steps in production services

Re-use and linking

Currently: GeoNames, GEMET…

Data re-use can be serendipitous!

From our domain (VIAF, UDC) or others (Eurovoc)

Multilingual resources are key for us

Europeana Data Model

• Representing objects & others: persons, places...

• Linking to internal or external data sources

• Separating original data from enrichments

• Enabling domain-specific data profiles

• Model re-uses existing vocabularies

http://pro.europeana.eu/edm-documentation

What is submitted to Europeana?

1. Thumbnails1. Thumbnails

2. Metadata2. Metadata

3. Links to digital objects online3. Links to digital objects online

Exemple

22

EDM data

Europeanaaggregation

“enriched”metadata

The “real” painting

DMF creator

DMF aggregation

digital representation

digital representation

data.europeana.eu

Europeana Linked Open Data Pilot

• Fully open metadata

• 2.4 M objects

• 200 individual providers

• 15 countries

data.europeana.eu

September 2012

• Europeana new Data Exchange Agreement apply

• Entire metadata is CC0

• Provided as dump files

Thank you

Antoine Isaac

aisaac@few.vu.nl