Linked (Open) Data Opportunities and challenges Makx Dekkers

Outline Basic notions Recent developments Comparing objectives Opportunities and risks Conclusions © 2011 Makx DekkersJourneés ABES 20112

BASIC NOTIONS © 2011 Makx DekkersJourneés ABES 20113

The idea and its history 1989: Tim Berners-Lee already talked about linking documents and data together ( 2001: Tim Berners-Lee and Ora Lassila introduced the Semantic Web ( 2006: Tim Berners-Lee presented the initial design issues (rules) for Linked Data ( © 2011 Makx DekkersJourneés ABES 20114

W3C Semantic Web initiative Objective – to create a universal medium for the exchange of data […] to smoothly interconnect personal information management, enterprise application integration, and the global sharing of commercial, scientific and cultural data Main results – Resource Description Framework (RDF), RDFa (RDF-in-HTML), SPARQL Query Language © 2011 Makx DekkersJourneés ABES 20115

Core Linked Data Specifications Transport – HTTP Hypertext Transfer Protocol Identification – URI Uniform Resource Identifier Description and linking – RDF Resource Description Framework Search and access – SPARQL Query Language for RDF © 2011 Makx DekkersJourneés ABES 20116

The four rules of Linked Data TBLs recommendations: 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 the standards (RDF*, SPARQL) 4.Include links to other URIs so that they can discover more things © 2011 Makx DekkersJourneés ABES 20117

The basic model of RDF Resource Description Framework triple: – Subject: the thing (resource) described – Predicate: the characteristic of the resource – Object: the value of the characteristic SubjectObject Predicate © 2011 Makx DekkersJourneés ABES 20118

Complex structures in RDF This presentation Makx Dekkers Barcelona Journées ABES ABES Montpellier May 2011 presenter partOf organizer location hometown date location © 2011 Makx DekkersJourneés ABES 20119

Linked (Open / Enterprise) Data Commonalities – Using Semantic Web technologies (RDF) – Linking information resources, people, places Differences – Open Data with open licenses; Enterprise Data mostly for closed, controlled environments – Open Data links to other Open Data, available for external use; Enterprise Data may link to external data but not openly available for external use © 2011 Makx DekkersJourneés ABES

Linked Data -- Open Data Linked Data: focus on technology – Semantic Web: Resource Description Framework, and other Web standards – Final solutions still under development Open Data: focus on strategy – Based on notion that sharing is important and benefits all – Technology is secondary © 2011 Makx DekkersJourneés ABES

The five-star system Source: © 2011 Makx DekkersJourneés ABES

The LOD diagram: 2007 Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. © 2011 Makx DekkersJourneés ABES datasets

The LOD diagram: 2008 Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. © 2011 Makx DekkersJourneés ABES datasets

The LOD diagram: 2009 Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. © 2011 Makx DekkersJourneés ABES datasets

The LOD diagram: 2010 Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. © 2011 Makx DekkersJourneés ABES datasets

RECENT DEVELOPMENTS © 2011 Makx DekkersJourneés ABES

W3C communities LinkingOpenData SWEO Community Project – Goal: to extend the Web with a data commons by publishing various open data sets as RDF on the Web and by setting RDF links between data items from different data sources ( Library Linked Data Incubator Group – to help increase global interoperability of library data on the Web ( © 2011 Makx DekkersJourneés ABES

More W3C communities Government Linking Data Working Group – to provide standards and other information which help governments around the world publish their data as effective and usable linked data ( Semantic Web Health Care and Life Sciences (HCLS) Interest Group – to develop, advocate for, and support the use of Semantic Web technologies for health care and life science (e.g. biology, medicine) ( © 2011 Makx DekkersJourneés ABES

Open Knowledge Foundation, okfn.org not-for-profit organization promoting open knowledge: any kind of data and content that can be freely used, reused, and redistributed Working and Interest Groups, e.g. – Open Data in Science, Open Government Data, Open Bibliographic Data, Cultural Heritage etc. CKAN.net: registry of open datasets and other knowledge resources © 2011 Makx DekkersJourneés ABES

Linked Data initiatives Predicate vocabularies (descriptors) Research Description and Access (RDA) The Bibliographic Ontology (BIBO) Dublin Corehttp://dublincore.org/ Object vocabularies (values) Virtual International Authority File (VIAF) Library of Congress authoritieshttp://id.loc.gov/authorities/ AgroVOC (agricultural terminology)e.g. DBPedia (based on Wikipedia)e.g. Bibliographic data LIBRIS Swedene.g. British Libraryhttp:// CrossRef (DOI metadata) © 2011 Makx DekkersJourneés ABES

More Linked Data initiatives Broadcasting, publishing BBChttp:// New York Timeshttp://data.nytimes.com/ Governments (small sample) USAhttp://data.gov/ Francehttp://opendata.paris.fr/ Finlandhttp://data.suomi.fi/ UKhttp://data.gov.uk/ Spain (Cataluña) Norwayhttp://data.norge.no Netherlandshttp:// Australiahttp://data.gov.au/ © 2011 Makx DekkersJourneés ABES

COMPARING OBJECTIVES © 2011 Makx DekkersJourneés ABES

Strategic aspects Linked Data Achieving global interoperability with minimal coordination Aggregating human knowledge Supporting democracy, transparency and accountability Enhancing and enriching information Enabling user-driven and user-generated applications © 2011 Makx DekkersJourneés ABES

Strategic aspects libraries Organizing information for use by specific users for specific goals Ensuring and maintaining quality Sustaining services economically Preserving information for the long term Providing trusted services © 2011 Makx DekkersJourneés ABES

Functional aspects Linked Data Searching distributed collections Following your nose – navigating links between pieces of content Distributing responsibility for making statements about things Leaving to the user whom and what to trust Leaving development of products and services to an open market (apps) © 2011 Makx DekkersJourneés ABES

Functional aspects libraries Describing information by professionals Bringing together and managing aggregations of information Selecting relevant information Mixing analogue and digital resources © 2011 Makx DekkersJourneés ABES

Technical aspects Linked Data Publishing and using machine-readable statements (data that speak for themselves) Focusing on Semantic Web technology Enabling inferences across large distributed data sets (Still to be done) Solving issues around harvesting, caching and real-time updating © 2011 Makx DekkersJourneés ABES

Technical aspects libraries Using proven technology to provide high- quality services Managing production systems and services Guaranteeing performance, uptime, consistency across data © 2011 Makx DekkersJourneés ABES

Agility versus sustainability In the Linked Data space: – Things move fast – Trial-and-error – Lots of development by volunteers (hackers) In the library domain: – Operational systems need to evolve – Need to handle legacy data – Development by professionals in managed projects © 2011 Makx DekkersJourneés ABES

Data versus services In the Linked Data space: – Focus on availability of raw data – Quality is secondary – Data and technology should lead to useful results In the library domain: – Focus on services – Quality is essential – Data and technology in support of the service © 2011 Makx DekkersJourneés ABES

Economic aspects In the Linked Data space: – Information wants to be free – a human right? – Short-term thinking: today is hot, yesterday is not – Focus on applications to create value out of data In the library domain: – Long-term view: sustainability is crucial – Public money to provide community services – Expected to do more with less money © 2011 Makx DekkersJourneés ABES

OPPORTUNITIES AND RISKS © 2011 Makx DekkersJourneés ABES

Strong points Linked Data Attempt to create a common technical platform for machine-readable data Lots of enthusiasm in publishing open data Promise of global interoperability Mix of researchers, user communities, hackers, professional data providers High visibility on political level © 2011 Makx DekkersJourneés ABES

Risks Linked Data Driven by technology, not by requirements Technology may not (yet) be stable – RDF 2.0? Operational issues far from solved (reliability, performance, quality, security, trust) Hope for general agreement across domains may not be realistic Promise may turn into disappointment © 2011 Makx DekkersJourneés ABES

Strong points libraries Long time operational experience in managing information Professional intermediaries between users and information needs Sustainable business models (albeit with eternally shrinking budgets) Long-term perspective: the past (legacy data) as well as the future (preservation) © 2011 Makx DekkersJourneés ABES

Risks libraries Technologies change rapidly New skills difficult to spread through the organization Some people see libraries as a thing of the past (the book museum) Underestimation of information handling skills Information overload, human intervention does not scale, need for better tools © 2011 Makx DekkersJourneés ABES

Meeting both worlds An example: Europeana.eu – Started out with domain perspectives (libraries, archives, museums, audiovisual archives) – Traditional approach (metadata mappings) works but insufficient – Using Linked Data approach preserves domain specifics but allows for generalization to support common services – Cross-domain (but co-ordinated) interoperability © 2011 Makx DekkersJourneés ABES

Europeana Data Model Classes Properties Simple example Complex example Source at: © 2011 Makx DekkersJourneés ABES

CONCLUSION © 2011 Makx DekkersJourneés ABES

Libraries and Linked Data Using Linked Data technology as the next step in connecting services Offering information management skills to the technology domain Creating a quality hub in the Linked Data space © 2011 Makx DekkersJourneés ABES

Best of both worlds Libraries providing stability and sustainability to Linked Data spaces Library professionals helping to manage the distributed collections Libraries delivering high-quality linked data to the Web Technologists to provide the next generation of systems and tools © 2011 Makx DekkersJourneés ABES

Linked (Open) Data: opportunity for libraries! Thank you! Makx Dekkers