A presentation given at Online Information 2011 in London.

1. Image by: ...-Wink-... @ Flickr
Linked Data as an enabling
framework for resource
discovery across
libraries, museums and
archives
Andy Powell (and Pete Johnston)
Eduserv
@andypowe11
www.eduserv.org.uk

2. What’s coming…
http://bit.ly/hmMvP1
• report on some work Pete Johnston and I
(both at Eduserv) undertook in March 2011
• on behalf of the JISC and RLUK Resource
Discovery Taskforce
• (which subsequently became “Discovery”)
• to develop some metadata guidelines for use
across libraries, museums, and archives
www.eduserv.org.uk

3. Functional requirement
• help libraries, museums and archives expose
existing metadata (and new metadata created
using existing practice) in ways that
– support the development of aggregator services
– integrate well with the web (and the emerging
web of data)
• note: NOT re-engineering cataloguing practice
in the LAM sectors
www.eduserv.org.uk

4. Guiding principles
• support the RDTF Vision
• in line with Linked Data principles
• based on the W3C Linked Open Data Star Scheme
• in line with Designing URI Sets for the UK Public
Sector
• take into account the Europeana Data Model and ESE
• be broadly in line with the notion of “making better
websites” across libraries, museums and archives
www.eduserv.org.uk

5. RDTF Vision
“making the most of UK scholarly and cultural
resources by best positioning their metadata for
discovery and reuse within the global
information ecosystem”
www.eduserv.org.uk

6. Linked Data
http://www.w3.org/DesignIssues/LinkedData.html
• use URIs as names for things
• use HTTP URIs so that people can look up
those names
• when someone looks up a URI, provide useful
information, using the standards
(RDF, SPARQL)
• include links to other URIs so that they can
discover more things
www.eduserv.org.uk

7. Linked Open Data Star Scheme
http://bit.ly/u1O7e3
• 1 star - make your stuff available on the Web
(whatever format) under an open license
• 2 star - make it available as structured data
(e.g., Excel instead of image scan of a table)
• 3 star - use non-proprietary formats (e.g., CSV
instead of Excel)
• 4 star - use URIs to identify things, so that people can
point at your stuff
• 5 star - link your data to other data to provide
context
www.eduserv.org.uk

8. Our draft RDTF proposal
• used the W3C Linked Open Data star scheme
as framework (at 3, 4 and 5 star levels)
• and suggested three approaches
– community formats
– RDF data
– Linked Data
• 196 comments – on pretty much all aspects of
the draft
www.eduserv.org.uk

9. Re-conceptualising the guidelines
Not-RDF RDF
Individual Item
Descriptions
Collections
of Descriptions
www.eduserv.org.uk

10. The draft guidelines
Not-RDF RDF
Individual Item Linked Data
Descriptions
Collections “bulk “RDF Data”
of Descriptions transfer”
www.eduserv.org.uk

11. The Web!
Not-RDF RDF
Individual Item “page per Linked Data
Descriptions thing”
Collections “bulk “RDF Data”
of Descriptions transfer”
www.eduserv.org.uk

12. Guiding principles
• support the RDTF Vision
• in line with Linked Data principles
• based on the W3C Linked Open Data Star Scheme
• in line with Designing URI Sets for the UK Public
Sector
• take into account the Europeana Data Model and ESE
• be broadly in line with the notion of “making better
websites” across libraries, museums and archives
www.eduserv.org.uk

13. Semantics vs. linking
• moving left to right across the quadrants…
– offers greater semantic precision within a more
consistent framework (RDF)
“page per Linked Data
thing”
“bulk “RDF Data”
transfer”
www.eduserv.org.uk

14. Linking vs. semantics
• moving bottom to top across the quadrants…
– promotes the individual descriptions (rather than
collections of descriptions) and encourages the
assignment of identifiers (i.e. URIs) to both those
descriptions and the things they identify
“page per Linked Data
thing”
“bulk “RDF Data”
transfer”
www.eduserv.org.uk

15. Possible adoption path
Not-RDF RDF
Individual Item “page per Linked Data
Descriptions thing”
Collections “bulk “RDF Data”
of Descriptions transfer”
www.eduserv.org.uk

16. “page Linked
Bulk transfer per
thing”
Data
“bulk “RDF
transfer” Data”
• “give us what you’ve got”
• serve existing community bulk-formats (e.g. files
containing collections of
MARC, MODS, BibTeX, DC/XML, SPECTRUM or EAD
records) or CSV over RESTful HTTP
• use sitemaps and robots.txt and/or RSS/Atom to
advertise availability and GZip for compression
• for CSV, provide a column called ‘label’ or ‘title’ so
we’ve got something to display
• give us separate records (for CSV, read ‘rows’) about
separate resources (where you can)
www.eduserv.org.uk

17. “page Linked
Page per thing per
thing”
Data
“bulk “RDF
transfer” Data”
• “build better websites”
• serve an HTML page (i.e. a description) for every “thing”
of interest over RESTful HTTP
• optionally serve alternative format(s) for each
description (e.g. a MODS or DC/XML record) at separate
URIs and link from the HTML descriptions using “<link
rel=“alternative” … />
• use “cool” ‘http’ URIs for all descriptions
• use sitemaps and robots.txt and/or RSS/Atom to
advertise availability
• optionally offer OAI-PMH server to allow harvesting
www.eduserv.org.uk

18. “page Linked
RDF data per
thing”
Data
“bulk “RDF
transfer” Data”
• “RDF bulk download”
• serve big buckets of RDF (as RDF/XML, N-Tuples or N-
Quads) over RESTful HTTP
• re-use existing conceptual models and vocabularies
where you can
• assign URIs to every “thing” of interest
• use Semantic Sitemaps and the Vocabulary of
Interlinked Datasets (VoID) to advertise availability of
the buckets
www.eduserv.org.uk

19. “page Linked
Linked Data per
thing”
Data
“bulk “RDF
transfer” Data”
• “W3C 5 star approach”
• serve HTML and RDF/RDFa for every “thing” of
interest over RESTful HTTP
• assign ‘http’ URIs to every “thing” (and every
description of a thing)
• follow “cool URIs for the semantic web”
recommended practice
• become part of the web of data - link to other
people’s stuff using their URIs
www.eduserv.org.uk

20. Possible adoption path
Not-RDF RDF
Individual Item “page per Linked Data
Descriptions thing”
Collections “bulk “RDF Data”
of Descriptions transfer”
www.eduserv.org.uk

21. Where are we headed?
• implication of previous slide is that “5 star”
Linked Data is where we want to be
• some good reasons for that
– rich semantic framework
– “follow your nose” approach to getting more info
– “small pieces loosely joined”
– link and be linked – data becomes “of” the web
– relatively easy re-use of other peoples’ ontologies
www.eduserv.org.uk

22. But…
• also need to remember that “the best is
sometimes the enemy of the good”
• recent web history tells us that uptake of
complex technologies can be a slow process!
• certainly been the case with the Semantic
Web and RDF
www.eduserv.org.uk

23. ‘Linked’ and ‘social’ can be a win
http://ogp.me/
• Open Graph Protocol
• as proposed by Facebook but now more
widely adopted
• good example of Linked Data underpinning
social activity (part of which is related to
discovery)
• but what’s more important – the fact it uses
RDF or the fact it uses the HTTP URI?
www.eduserv.org.uk

24. I would suggest the latter
www.eduserv.org.uk

25. Conclusions
• true Linked Data is a good aim for
libraries, museums and archives…
• …but our emphasis should be on the ‘linked’
in short term
• encouraging more item-level material on the
Web with cool URIs (even if only in largely
human-readable form)
• richer Linked Data can then emerge over time
www.eduserv.org.uk

26. Image by: ...-Wink-... @ Flickr
Questions?
www.eduserv.org.uk