On Libraries & Linked Data

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Oct 21, 2013 (3 years and 7 months ago)

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On Libraries & Linked Data

Antoine Isaac



UB Utrecht, April 6, 2011

Who am I?





Europeana


Web & Media Lab
, Vrije Universiteit Amsterdam



W3C Library Linked Data group


(2006
-
2009)
W3C Semantic Web Deployment group

SKOS


aisaac@few.vu.nl

Demo

Following one’s nose to subject heading lists as linked data


American LCSH

http://id.loc.gov/authorities/sh85145447#concept



French RAMEAU

http://stitch.cs.vu.nl/vocabularies/rameau/ark:/12148/cb11931913j



German SWD

http://d
-
nb.info/gnd/4064689
-
0



Agrovoc

http://aims.fao.org/aos/agrovoc/c_8309



STW

http://zbw.eu/stw/descriptor/14188
-
0



Further on to DBPedia

http://dbpedia.org/resource/Water


Demo (fallback option)

Subject heading lists as SKOS linked data


American LCSH




http://id.loc.gov


French RAMEAU:



http://stitch.cs.vu.nl/rameau


German SWD:




http://d
-
nb.info/gnd/



mapped using manual links from the MACS project









http://macs.cenl.org



Starting from
http://id.loc.gov/authorities/sh85014310#concept







Linked Data?

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/



(Linked) Data Representation


That subject heading data follows a link
-
intensive
data model

Uniform resource identifiers (URI)

Resource Description Framework (RDF)

(Linked) Data Representation


Use more
-
or
-
less the same standard vocabulary

Simple Knowledge Organization System (SKOS)

http://www.w3.org/2004/02/skos/


For representing thesauri, classifications, etc. on the
Semantic Web

A SKOS graph

animals

cats


UF domestic cats


RT wildcats


BT animals


SN used only for domestic cats

domestic cats


USE cats

wildcats

SKOS mappings

SKOS provides conceptual links to bridge across different
contexts

KOS 1:

animals

cats

wildcats

KOS 2:

animal

human

object

Links in the data


Links in the data



Growing interest for linked data in the
library community

Linked Library Cloud beginning 2008


[Ross Singer, Code4Lib2010]

http://code4lib.org/conference/2010/singer

Linked Library “sector” in 2010


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


Libraries and LD, the perfect match?


Libraries have been producing (meta)data
for ages


Libraries (often) produce
high
-
quality
metadata



Libraries and LD, the perfect match?


Library metadata was
locked
in record silos


But it maintain links to the outside world


Bibliographic and web references


Shared vocabularies


Same books!


Libraries and LD, the perfect match?

LD is about


Citing object


Linking to them


Re
-
using data


Think of web
-
native union catalogues


Johan Stapel, Koninklijke Bibliotheek (now bibliotheek.nl)

A vision for the Dutch National Library


A web of cultural heritage data?

?

?

The current portal



Towards semantic search: facets


Building a search engine on top of metadata is difficult

Intrinsic quality problems: correctness, coverage


Especially when data is so heterogeneous

100s of formats

From flat 5
-
fields records to 100
-
nodes XML trees

Language issue!


We currently use a simple, flat interoperability format

Quick
-
win quickly showing its limits



We can better use institutions’ original metadata


Accommodate their different practices

Data structures and semantics


Access objects via a semantic layer of vocabularies for
subjects, persons, places…


Semantic ThoughtLab:

experimenting solutions

Towards semantics
-
enabled search

Building a "semantic layer" to help accessing content

Towards semantics
-
enabled search


Enhance access to Europeana content by semantics


Query expansion, clustering of results



Exploiting various types of relations


"located in", "lived in", "is more specific concept"…



Semantics are already there, in metadata and
"controlled vocabularies" used in metadata


Thesauri, classifications…



Requires to make it properly machine
-
accessible

Europeana Data Model

Trying to evolve towards RDF and Linked Data


Representing objects, persons, places, etc. as
resources


Linking and re
-
using external sources


(Re
-
using) richer data modeling features

SKOS, CIDOC
-
CRM, OAI
-
ORE


Enabling domain
-
specific data profiles


Separating original data from enrichments


http://version1.europeana.eu/web/europeana
-
project/technicaldocuments/


Prototype: Europeana Thought Lab

http://europeana.eu/portal/thought
-
lab.html

Clustering of results

Baseline: matching concepts' label

Controlled place name from a
vocabulary at the Rijskmuseum

Metadata for the object

A "more specific Egypte"?


A "more specific Egypte"?


Metadata for the object

A place more specific than the Egypt one


Semantic information on the Giza
place in the Rijskmuseum Vocabulary

Following other relations


Following other relations
-

creator


Metadata for the object

Controlled person name from a
vocabulary at the Rijskmuseum

Following other relations
-

match


Information on Gustave Le Gray
from the Rijskmuseum Vocabulary

Matched to a "Gustave Le Gray"
from another Vocabulary

Enabling bits & pieces

Exploiting semantic links in CH vocabularies

Concept “Giza” narrower than concept “Egypte”


Mapping/alignment between CH vocabularies

Louvre’s “Égypte” equivalent to Rijksmuseum’s “Egypte”


Enrichment of existing metadata

The string “Egypt” in a metadata record indicates the concept of
Egypt defined in Rijksmuseum thesaurus

Challenge #1: Linking


Challenge #1: Linking

Manual mapping of large vocabularies is labour
-
intensive


LCSH, RAMEAU and SWD mapped in the MACS project


http://macs.cenl.org



SWD and DDC mapped in the CRISS
-
CROSS project






http://linux2.fbi.fh
-
koeln.de/crisscross/



Automatic linking is not perfect but can help


STW, AGROVOC…


Some studies (and further pointers) for automatic library
thesaurus alignment in the STITCH project

http://stitch.cs.vu.nl



Challenge #1: Linking



(Semi
-
)automatic techniques are necessary to


Connect objects to vocabularies (esp. for legacy data)


Connect objects themselves together



Crowdsourcing?



Making the way librarians create metadata evolve?



Linking strategy for libraries?


Linking strategy for libraries?


Links to library
-
originated sources


VIAF, LCSH, DDC, UDC, Worldcat, PND…



Links to resources from cultural environment


Museums, archives


Scientific communities: bibliographic data & research data


Publishers


Europeana and other aggregators



Semantic Annotation

Conclusion?



Linked Data won’t not solve everything right now



Just a set of techniques and a vision for better
sharing, cross
-
linking and re
-
use data, fitting the web



Which is not bad!

If we stop here, thanks for your attention!







Any (more) questions?

Some references


W3C Library LD Incubator

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


1
-
year group


OCLC, LC, VU Amsterdam, DNB, etc.



help increase global interoperability of library data on the
Web


bringing together people involved in Linked Data

in the
library community and beyond


building on existing initiatives and collaboration tracks for the
future

Library LD

Use Cases


LLD use cases and case
studies (work in progress)




JISC cases for open
bibliographic data

http://obd.jisc.ac.uk


http://www.w3.org/2005/Incubator/lld/wiki/UseCases

Useful vocabularies to express data


Dublin Core


SKOS


BIBO


OAI
-
ORE


FOAF


MADS

In progress


RDA vocabularies


FRBR@IFLA

Cf. Linked Open Vocabularies

Note: vocabularies can be combined and articulated together



dublincore.org/

www.w3.org/2004/02/skos/

bibliontology.com/

www.openarchives.org/ore/

www.foaf
-
project.org/

www.loc.gov/standards/mads/rdf/

metadataregistry.org/rdabrowse.htm



labs.mondeca.com/dataset/lov/

Datasets


Controlled vocabularies (thesauri, etc.)

LCSH, DDC, Agrovoc, VIAF, GND


Bibliographic data

Nat. Libraries of Hungary, Sweden



Trying to keep track of some on CKAN

http://ckan.net/group/lld



In the Netherlands


DEN, Bibliotheek.nl, KB, Vrije Universiteit Amsterdam, Beeld
en Geluid, UvA Library



Amsterdam Museum as Linked Data








http://semanticweb.cs.vu.nl/lod/am/




Dutch Culture Link








http://sites.google.com/site/dclod11/


Dublin Core 2011



http://dcevents.dublincore.org/index.php/IntConf/dc
-
2011


Pictures


http://www.europeana.eu/portal/record/03903/8C5C6AEFF6B50DCCEDF6
A23A99DD3A2D66AEB2CC.html


http://www.europeana.eu/portal/record/03912/E9666896A50FDDE5F7F1
5A17C11219A7FBCBBC50.html

(Europeana links give access to resources on original sites)

First Demo pointers


American LCSH




http://id.loc.gov


French RAMEAU:



http://stitch.cs.vu.nl/rameau


German SWD:




http://d
-
nb.info/gnd/



Agrovoc:






http://aims.fao.org/



STW:







http://zbw.eu/stw/



DBPedia:






http://dbpedia.org/