Forging a Path for Linked Open Data at the DPLA Gretchen Guegen, Data Services Coordinator, Digital Public Library of America (DPLA)

1. Forging a Path for Linked
Open Data at DPLA
Gretchen Gueguen
Data Services Coordinator
Digital Public Library of America

5. DPLA by the numbers
8,000,000+ records
23 hubs and counting
1300+ contributing institutions

6. DPLA by the numbers
…3 major metadata schemas, 1
product-specific formats, 5 institution-specific
formats

7. DPLA’s Metadata Application
Profile
• Originally developed between 2012
and 2013
• Based on the Europeana Data Model
• Currently in version 3.1
• Undergoing update to version 4

8. MAP v3.1

9. MAP v4

10. Namespaces
• Content in RDF (cnt): http://www.w3.org/2011/content#
• Dublin Core (dc): http://purl.org/dc/elements/1.1/
• Dublin Core Terms (dcterms): http://purl.org/dc/terms/
• DCMI Type Vocabulary (dcmitype): http://purl.org/dc/dcmitype/
• Europeana Data Model (edm): http://www.europeana.eu/schemas/edm/
• Geonames (gn): http://www.geonames.org/ontology#
• Open Annotation (oa): http://www.w3.org/ns/oa#
• OAI Object Reuse and Exchange (ore): http://www.openarchives.org/ore/terms/
• Resource Description Framework (rdf):
http://www.w3.org/1999/02/22-rdf-syntax-ns#
• RDF Schema (rdfs): http://www.w3.org/2000/01/rdf-schema#
• Simple Knowledge Organization System (skos):
http://www.w3.org/2004/02/skos/core#
• World Geodetic System (wgs84): http://www.w3.org/2003/01/geo/wgs84_pos#

11. Expansion of Classes
• Place
• Agent
• Concept

13. Examples of Provided Subjects
<dc:subject>figures (representations); trees; vines</
dc:subject>
<dc:subject authority=“lcsh” valueURI=“http://
id.loc.gov/authorities/subjects/sh85073038”> Korea--
History--Japanese occupations, 1910-1945</
dc:subject>

14. Examples in JSON-LD
"subject":[
{
”providedLabel” : ”figures (representations)”
},
],
"subject":[
{
”concept” : ” Korea--
History--Japanese occupations, 1910-1945”
“scheme” : “http://id.loc.gov/authorities/subjects”
“exactMatch” : “http://id.loc.gov/authorities/subjects/sh85073038”
},
],

17. Enriched data; close
match
Original Label

18. Standardized Rights Metadata
• Knight
Foundation-funded
project to
develop
standardized
namespace
for rights
metadata
and a list of
URIs for
standard
declarations

20. API
• Native rdf triplestore serialized into JSON-LD
• Currently based on MAPv3.1
• Public website uses JSON-LD api
• Also available through the API directly
• Entire datastore available for download
• Implementation of MAPv4 will occur in
stored data, but will be mapped to
MAPv3.1 for use in the API for the near
future

23. Future Steps
• Source of LOD?
• Portal with LOD?
• Service for adding LOD to library
bibliographic records?