Publishing Linked Data LInked *Open* Data

1. Publishing and Using
Linked Open Data
Richard J. Urban, Ph.D.
School of Library and Information Studies
Florida State University
rurban@fsu.edu
@musebrarian
#lod4h

2. January 10, 2013
Thursday’s Schedule
• 9-10:30 am Class Session: Publishing Linked Data
& Linked Data Applications
• 10:30-10:45 am break
• 10:45-Noon Class Session: Linked Open Data
• Noon- 1:00 pm Lunch
• 1:00-3:00 pm Class Session: Open Project Studio
• 3:00-3:15 pm Break
• 3:15-5:00 pm Class Session: Open Project Studio
• 5:30-7:30 pm DHWI Banquet
Humanities Plain and Simple
Location: Colony Ballroom 2203, Stamp Student Union
#lod4h

3. PUBLISHING LINKED DATA &
LINKED DATA APPLICATIONS
#lod4h

4. http://linkeddatabook.com/editions/1.0/#htoc61
#lod4h

5. Connect to Existing Data
• SIMILE RDFizers
http://simile.mit.edu/wiki/RDFizers
• D2RQ non-RDF relational data to RDF
http://d2rq.org/
• OAI2LOD
https://github.com/behas/oai2lod
#lod4h

6. Publish Files
• What’s the right syntax for your audience?
• How to version instance and ontology
data?
• Thinking about URIs
– URIs that follow your classes
– Not based on underlying software
– Designed to persist
– URIs for resources vs. URIs for data
#lod4h

7. Triplestores: Questions to ask
• What methods can be used to store data?
– In Memory, SQL,mySQL, Postgres, etc.
• What level of expressivity is supported?
– RDFs, OWL Lite, OWL DL, etc.
– Reasoner support
• What rule languages are supported?
– SWRL, etc.
• Support for contexts/named graphs
• What does the API support?
#lod4h

8. Triplestores
• Jena
http://jena.apache.org/
• Sesame
http://www.openrdf.org/
• W3C Triplestore resource
http://www.w3.org/2001/sw/wiki/Category:
Triple_Store
• Virtuoso (proprietary)
http://virtuoso.openlinksw.com/
#lod4h

9. Interfaces
• Drupal 7
http://drupal.org/project/rdf
– See also RDF specific modules
• Pubby
http://wifo5-03.informatik.uni-
mannheim.de/pubby/
• Semantic Wiki
http://semantic-
mediawiki.org/wiki/Semantic_MediaWiki
#lod4h

10. Embedding Linked Data
• RDFa
– http://www.w3.org/TR/xhtml-rdfa-primer/
• Schema.org
• Schema.org + RDF
http://schema.rdfs.org/
#lod4h

11. LINKED OPEN DATA
#lod4h

12. Linked Open Data Criteria
★ Available on the web (whatever format), but
with an open license
★★ Available as machine-readable structured data
(e.g. excel instead of image scan of a table)
★★★ as (2) plus non-proprietary format (e.g. CSV
instead of excel)
★★★★ All the above plus, Use open standards from
W3C (RDF and SPARQL) to identify things, so
that people can point at your stuff
★★★★★ All the above, plus: Link your data to other
people’s data to provide context
#lod4h

13. IP
• Risk Management
• What’s your risk tolerance?
– Tolerance of your institution?
• Not saying anything about your data IP
isn’t much better than a restrictive license.
#lod4h

14. Licensing Data
• Open Data Commons
http://opendatacommons.org/
• Creative Commons 0
http://creativecommons.org/choose/zero/
#lod4h

15. Humanities Data Citation Practices
• Where do we stand?
• How to best give attribution when we use
triples from another source?
– Published documentation
– Provenance metadata
• What does this attach too?
• DCMI Provenance Metadata
http://dublincore.org/groups/provenance/
• W3C Provenance WG
http://www.w3.org/2011/prov/wiki/Main_Page
#lod4h

16. For the long run
• DH Data Curation Handbook - Policy,
Practice, and
Lawhttp://guide.dhcuration.org/legal/policy/
• How will data be maintained over the long
term.
• Clear licenses can facilitate preservation.
#lod4h

17. Economics of Linked Data
• How to adapt Linked Data to closed
publication models?
– Make identifiers publically available.
– Provide some limited information when the
URI is used.
– Release taxonomies/vocabularies as separate
data.
#lod4h