Functional requirements for bibliographic linked data: the FR family

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Functional requirements for
bibliographic linked data: the FR
family and the Semantic Web
Gordon Dunsire
Presented to the ALCTS FRBR Interest
Group, ALA Annual, 24 June 2011
Overview
Background
Resource Description Framework
Representing Functional Requirements for the
Semantic Web
Some issues
Legacy catalogue records
FRAD
FRBR
Does not cover
“authorities”
Does not cover
subjects
FRSAD
FR
Consolidated
model
Semantic
recapitulate
1998Web versions
2009
2010 this sequence:
2012?
*
*
*
*
Earlier models in use before later models published
Later models re-use elements from earlier models
Reflects semantic development over time
Provides learning curve for FRBR Review Group
Background
RDA: resource description and access is based
on FRBR and FRAD
Bibliographic metadata content guidelines
DCMI RDA Task Group asked to develop an
RDF representation of RDA
Following the “London” meeting in April 2007
Stimulated creation of “FRBR namespaces
project”
To develop RDF representation of FRBR
RDF
Resource Description Framework
Basis of the Semantic Web
Metadata expressed as “atomic” statements
A simple, single, irreducible statement
The creator of this work is R. Shankar
Constructed in 3 parts
“Triple”
RDF triples
The creator of this work is R. Shankar
Subject of the statement = Subject: This work
Nature of the statement = Predicate: has creator
Value of the statement = Object: R. Shankar
This work – has creator – R. Shankar
subject – predicate – object
RDF requires the subject and predicate of a triple
to have machine-readable identifiers
Uniform Resource Identifier (URI)
Object of triple can be a URI, or a literal string like a
title
RDF properties and classes
A predicate is called a property
Properties link two things
A specific work with a specific creator
This work <-> R. Shankar
A generic type of thing is called a class
Works, Persons, Places, etc.
Properties can specify which class the subject
and object of a triple should belong to
Subject “domain”; object “range”
Methodology (1)
 Open Metadata Registry used for basic representation
in RDF
Same approach as RDA
Provides URI assignment; labels, definition, scope note,
property range and domain
 FR family are entity-relationship models
Entity => RDF Class
E.g. FRBR Work
Entity attribute => RDF property
E.g. FRBR has-intended-audience
Entity-entity relationship => RDF property
E.g. FRBR is-realized-through (Work-Expression)
Classes
Properties
FRBR Groups are not (super-)classes [FRBR Review Group]
Group 1 entities are not classes [some ontologists]
3.2.5 Person
The fifth entity defined in the
model is person: an individual.
The entity defined as person
encompasses individuals that are
deceased as well as those that are
living.
Entity => Class
4.4.12 Capture mode
Capture mode is the means used to
record notation, sound, or images
in the production of a
manifestation (e.g., analogue,
acoustic, electric, digital, optical
etc.).
Attribute => Property
Label
Definition
Scope note
Label
Definition
Scope note
Verbalised label
URI
URI for Manifestation
Spanish translation of label
- URI remains the same
Methodology (2)
 Terminology of labels, definitions and scope notes
based as closely as possible on source documentation
E.g. Property label = “has” + attribute name
 Classes and properties declared for prior model(s) reused in current model
E.g. FRAD re-uses URIs from FRBR namespace
E.g. FRBR Expression; FRBR has-key
 No re-use of RDF resources from external community
namespaces such as Dublin Core Terms
Equivalences likely to be established later
Methodology (3)
FR attribute properties have domain but no
range
Required by the model for extensibility
E.g. FRBR has-key (domain = Work)
Relationship properties have domain and
range
E.g. FRBR is-realized-through (domain = Work;
range = Expression)
General, non-technical issues
Consistency within documentation
Written for human consumption; evidence of variable
phrasing to make it more readable
E.g. “prior”, “preceding”, “first”
Consistency of labels of RDF resources
E.g. “has a reproduction” (regular) vs “has
reproduction” (irregular)
Documentation refers to sub-types of entity
E.g. “musical work”, “serial”
First pass: sub-type => sub-class
But wrong due to semantic overlap
Opaque URIs
http://iflastandards.info/ns/fr/frbr/frbrer/P1001
frbrer:P1001
Not http://iflastandards.info/ns/fr/frbr/frbrer/Work
IFLA operates in a multilingual environment
Anglophone bias avoided
Labels, etc. in English (@en), but no problem in
accommodating translations
Allows subsequent changes to alternative and
preferred labels without causing confusion
URI must not change!
Linking the FR models
Relationships between separate FR model
classes and properties are declared with RDF
equivalence and hierarchical properties
E.g. owl:sameAs, rdfs:subClassOf
E.g. FRAD class Corporate Body seems to be a
sub-class of FRBR Corporate Body
Will inform the consolidated model
Which may also require additional classes and
properties
RDA issues
DCMI RDA Task Group has declared parallel
FRBR classes within RDA namespace
Could not wait for FRBR RDF resources to be
approved
JSC to decide whether to substitute FRBR namespace
resources, or declare equivalence
Conflict with FRBR in RDA implementation
scenarios?
RDA Manifestation “embodies” Work and
Expression; FRBR allows only Expression
Legacy catalogue records
Domain and range of FR (and RDA) properties
inhibit use for creating triples from nonFRBRized catalogue records
Need separate URIs for each specific Work,
Expression, Manifestation, and Item
Solution: equivalent properties with no
domain or range
Need just a URI for the specific resource described
RDA has such unbounded properties
Thank you
[email protected]
 FRBR Review Group
http://www.ifla.org/en/frbr-rg
 Open Metadata Registry
http://metadataregistry.org/
 Library Linked Data Incubator Group
http://www.w3c.org/2005/Incubator/lld/
Sponsors
ALA
Cataloging & Classification Quarterly
MARCIVE, Inc.
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