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Linked Library Data. Modeling Metadata for the [Semantic] Web. Presented 2010-11-19 Columbia University Digital Library Seminar Series Corey A Harper. Topical Overview. Semantic Web Intro Linked Open Data Graphs: Entity – Attribute – Value A Few Examples Library Data.
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Linked Library Data Modeling Metadata for the [Semantic] Web Presented 2010-11-19Columbia University Digital Library Seminar Series Corey A Harper
Topical Overview • Semantic Web Intro • Linked Open Data • Graphs: Entity – Attribute – Value • A Few Examples • Library Data Harper - Linked Library Data - Columbia University
Topical Overview (cont) • Linked Library Data • SKOS and Authority Control • FRBR and Bibliographic Data • National Libraries • Resource Description and Access (RDA) • Dublin Core Metadata Initiative Harper - Linked Library Data - Columbia University
Semantic Web • TBL’s original vision • “Weaving the Web” – 1999 • Then: Focus on Machine Reasoning • Scientific American Article • Now: Focus on things & links • Reasoning becoming lower level Harper - Linked Library Data - Columbia University
Semantic Web • Originally: • Metadata standard built on XML • Metadata about “Web” things • Eventually: • Metadata about all things • Metadata about relationshipsbetweenthings Harper - Linked Library Data - Columbia University
Semantic Web Terminology • Resource: Any thing • Class: Abstraction of a type of thing • Individual: An instance of a class • Property: An attribute of an individual • Ontology: A domain specific collection of classes and properties • Statement/Triple: • A Resource (subject) - Nodes • A Property (predicate) - Arcs • A Value (object) - Nodes Harper - Linked Library Data - Columbia University
Semantic Web Terminology • Graphs: Representations of statements about resources • Nodes: The Subjects and Objects in a Graph • Arcs: The Predicates in a Graph • Literals: “Objects” represented as strings (constant values) rather than things (URI References) • Domains and Ranges: Constraints on Nodes • For Example… Harper - Linked Library Data - Columbia University
RDF • Resource Description Framework • Formally Begun in 1999 • Ideas from 1995 • Finalized in 2004 • Frighteningly complex at times… • “Directed Labeled Graphs” Harper - Linked Library Data - Columbia University
SemWeb Value Proposition • Formally Modeled (Meta) Data • Formal Semantics Declaration • Increased Granularity compared to record-based Metadata • Improved Interoperability Harper - Linked Library Data - Columbia University
“The vast bulk of data to be on the Semantic Web is already sitting in databases … all that is needed [is] to write an adapter to convert a particular format into RDF and all the content in that format is available.” -Tim Berners-Lee in an interview with the Consortium Standards Bulletin Harper - Linked Library Data - Columbia University
Linked Open Data • 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. • Include links to other URIs. so that they can discover more things. http://www.w3.org/DesignIssues/LinkedData.html Harper - Linked Library Data - Columbia University
Linked Data Cloud • Automated generation • Comprehensive Knowledge Archive Network (CKAN) • Vocabulary of Interlinked Datasets (voiD) • Basically, catalog your metadata! • Recent criticism: data quality Harper - Linked Library Data - Columbia University
Data in the Cloud • Hubs in the May 2008 Version: • FOAF • DBPedia • Myriad Sources coming online: • Thompson Reuters • New York Times • British Broadcasting Corporation • Google and Facebook • More and More Library Data • Geonames • MusicBrains Harper - Linked Library Data - Columbia University
DBpedia • Structured Wikipedia Data • Genres, Influences, External Links • Multi-lingual / Multi-script labels • Rich Semantics • Many linkages to other datasets Harper - Linked Library Data - Columbia University
DBpedia • 3.4 Million “things” described • Ontology based on “infoboxes” • 1.5 million things classified • Approx. 50,000 “Properties” • Approx. 1,200 defined in ontology • Brief Example Harper - Linked Library Data - Columbia University
Domain Modeling • Starting from application / goal / function “To guide and evaluate our designs, we need objective criteria that are founded on the purpose of the resulting artifact, rather than based on a priori notions of naturalness or Truth.” – Gruber, 1993 • Does this apply to Libraries? FRBRer? Harper - Linked Library Data - Columbia University
DBPedia Model • Partial basis in data entry conventions • InfoBox’s, and InfoBox Templates • Metadata Entry Format • Partial source of Ontology • Class Structure • Vocabulary Design Harper - Linked Library Data - Columbia University
DBpedia • 3.4 Million “things” described • Ontology based on “infoboxes” • 1.5 million things classified • http://wiki.dbpedia.org/Ontology • Approx. 50,000 “Properties” • Approx. 1,200 defined in ontology Harper - Linked Library Data - Columbia University
More Examples • British Broadcasting Corporation • Programmes, Music, Wildlife • Google Refine • Data.gov and data.gov.uk • NY Times Harper - Linked Library Data - Columbia University
What *things* are in our data??? Harper - Linked Library Data - Columbia University
…Librarydata is extremely complicated Harper - Linked Library Data - Columbia University
Bibliographic Data • Rich stores of MARC, MODS, &c. • Robust Controlled Vocabularies • Subject Heading lists • Code lists • Thesauri • Emerging data model in FR* Harper - Linked Library Data - Columbia University
Bibliographic Vocabs • Bibliographic Ontology • Zotero, Omeka, EPrints and Others • FRBR – unofficial • And now Official (Thank you IFLA!) • ISBD Harper - Linked Library Data - Columbia University
Library Authority Data “Include links to other URIs. so that they can discover more things.” Short of providing and linking to URIs, this *is* authority data. This is what our authority files are for. Harper - Linked Library Data - Columbia University
Library Controlled Vocabularies: Benefits • Reputation - Trusted Tradition • Mature - Time tested and carefully developed • General & Comprehensive - Cover large knowledge spaces Harper - Linked Library Data - Columbia University
SKOS • Simple Knowledge Organization System • Properties and Classes for describing Controlled Vocabulary skos:primaryTopic RDF Page skos:person Harper - Linked Library Data - Columbia University
LCSH in Dublin Core • Encoding Scheme for DC Subject • No easy way to draw on equivelent terms and cross-references • Abstract Model, RDF and SKOS could enable applications to make use of the whole vocabulary Harper - Linked Library Data - Columbia University
LCSH as a Web Service! • Uses principles of linked data • lcsh.info -> id.loc.gov • People noticed when taken down • Links to French Subject Headings • URIs for Literal String lookup • http://id.loc.gov/authorities/label/World Wide Web Harper - Linked Library Data - Columbia University
Other Vocabularies • Thesaurus for Economics • French Subject Headings • Swedish Subject Headings • IconClass (not on web yet) • OCLC Terminology Services • Dewey Decimal Classification • Virtual International Authority File Harper - Linked Library Data - Columbia University
Linked Library Data • VIAF, LCSH, MARC Codes • Open Library, XC, Kualli OLE • Library of Congress, OCLC • Hungarian, German, British, Swedish National Libraries • Formalized Efforts: W3C, IFLA & RDA Harper - Linked Library Data - Columbia University
Image courtesy of Martin Malmstemhttp://blog.libris.kb.se/semweb/?p=7 Kungliga Biblioteket Harper - Linked Library Data - Columbia University
National Széchényi Library “Our RDFDC, FAOF and SKOS statements are linked together. Our name authority is matched with the DBPedia name files and URI aliases are handled as owl:sameAs statements.” -Adam Horvath Harper - Linked Library Data - Columbia University
W3C LLD XG • “Incubator Group” • Membership: • Researchers, Consultants, Librarians • National Libraries: Germany, France, LoC, Sweden • OCLC & IFLA Harper - Linked Library Data - Columbia University
W3C LLD XG Goals • Collecting, Curating and Clustering over 50 Use Cases • Mining use cases for functional requirements and design patterns • Recommendations to W3C • Should lead to Working Groups Harper - Linked Library Data - Columbia University
RDA Slides Adapted from Diane Hillmann RDA Development RDA elements, roles and vocabularies have been provisionally registered IFLA FRBRer and ISBD elements and vocabularies have been officially registered Discussions about long term maintenance of both RDA and the vocabularies Effort to create multi-language RDA Vocabularies Harper - Linked Library Data - Columbia University
RDA Elements Listing 334! Harper - Linked Library Data - Columbia University
RDA Elements Listing Base material 334! Harper - Linked Library Data - Columbia University
Detail: Base Material Harper - Linked Library Data - Columbia University
Detail: Base Material URI Harper - Linked Library Data - Columbia University
RDA Base Material Vocabulary Harper - Linked Library Data - Columbia University
RDA WEMI Relationships Harper - Linked Library Data - Columbia University