Tim Berners-Leehttp://www.w3.org/People/Berners-Lee/card#i http://viaf.org/viaf/85312226/ LCCN: no 99010609
Four Rules • 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. http://www.w3.org/DesignIssues/LinkedData.html
Graph• The collection of statements (triples)• Shows the connections between things• We understand the connections, because the predicates have unambiguous meaning• Follow your nose and expand the graph
Schemas/Vocabularies• No real similarity to XML Schema • Common source of confusion (e.g. Dublin Core)• No “validation”, per se • constraints only apply for properties and classes, not resources • Unless the statements contradict each other• Mix and match vocabularies to ﬁll out the description across domains
• Dublin Core• Bibliontology• FOAF• SKOS• Good Relations• Music Ontology, etc.
Open World Assumption• Cannot assume that any source has all of the facts about a resource• Reuse of identiﬁers allows the augmentation of datasets• There is no “document”, because it’s always a work in progress
Disclaimers• There are currently no standards in actual use• This is not an attempt to “catalog”, merely to model existing data • And a sketchy one at that• No desire to roundtrip, etc.• Just make something that links our data and allows it to be consumed by others
@preﬁx rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .@preﬁx dcterms: <http://purl.org/dc/terms/> .@preﬁx owl: <http://www.w3.org/2002/07/owl#> .@preﬁx skos: <http://www.w3.org/2004/02/skos/core#> .<http://id.loc.gov/authorities/sh2008112104#concept> dcterms:created "2008-03-11T00:00:00-04:00"^^<http://www.w3.org/2001/XMLSchema#dateTime> ; dcterms:modiﬁed "2008-03-12T08:08:09-04:00"^^<http://www.w3.org/2001/XMLSchema#dateTime> ; dcterms:source "Work cat.: How to build a rocket, 2001"@en ; a skos:Concept ; owl:sameAs <info:lc/authorities/sh2008112104> ; skos:inScheme <http://id.loc.gov/authorities#conceptScheme>,<http://id.loc.gov/authorities#topicalTerms> ; skos:prefLabel "Space ﬂight to the moon--Juvenile literature"@en .
id.loc.gov• Label lookup service • http://id.loc.gov/authorities/label/ Astronauts--United%20States-- Biography--Juvenile%20Literature redirects to http://id.loc.gov/authorities/ sh2007100949#concept• Full data dumps available
@preﬁx rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .@preﬁx foaf: <http://xmlns.com/foaf/0.1/> .@preﬁx rdaEnt: <http://RDVocab.info/uri/schema/FRBRentitiesRDA/>.<http://viaf.org/viaf/158349825> a rdaEnt:CorporateBody, foaf:Organization ; foaf:name "Apollo Project (Spojené státy americké)", "ApolloProject (U.S.)", "Progetto Apollo (U.S.)", "Project Apollo", "ProjectApollo (Spojené státy americké)", "Project Apollo (U.S.)", "Spojenéstáty americké. Project Apollo", "United States. Project Apollo" .
Linked MARC Codes• URIs are based on the code, so no lookups are necessary• GACs, Countries, Languages, Musical Genres, Instrument & Voices, Audience, Frequency, and Form of Item• “Ofﬁcial” resources available at id.loc.gov for Languages, GACs and Countries • as SKOS:Concepts
RDA Elements• Useful for properties that are speciﬁc to library data (statementOfResponsibility, etc.)• Metric crap-tonne of properties • 459, to be exact • very few deﬁned domains or ranges • lots of duplication from other vocabs (NIH)