March 22, 2005

SKOS Core - minor edit

deprecated a comment on skos:inScheme - comment was based on mistaken understanding about relationship between skos:inScheme and rdfs:isDefinedBy

Categories SKOS Changelog
Posted by ajmiles at 04:01 PM | Comments (0)

February 25, 2005

SKOS Core - domain of skos:subject now unconstrained

The domain of the property skos:subject has been changed to be unconstrained (was foaf:Document). The range of the inverse property skos:isSubjectOf has been changed in the same way.

See also the discussion under http://lists.w3.org/Archives/Public/public-esw-thes/2005Feb/0058.html and all subsequent in thread.

Categories SKOS Changelog
Posted by ajmiles at 01:15 PM | Comments (0)

December 17, 2004

SKOS Core: Update to some term definitions and comments

A number of small changes have been made to the definitions and comments of some of the SKOS Core terms. These changes have been made mainly to refine the meaning and scope of these terms, and to bring them in line with the current development of the SKOS Core Guide.

Categories SKOS Changelog

The CVS change log reporting these changes is reproduced below.

----------------------------
revision 1.36
date: 2004/12/17 13:43:58; author: ajm65; state: Exp; lines: +11 -3
Change to skos:related - Changed the definition to mention 'associative relationships', because previous definition too broad, and also to bring in line with BS8723 definition of 'associative relationships'.
----------------------------
revision 1.35
date: 2004/12/17 13:37:39; author: ajm65; state: Exp; lines: +8 -2
Change to skos:OrderedCollection - The text 'where both the grouping and the ordering are meaningful' added to the definition.
----------------------------
revision 1.34
date: 2004/12/17 13:34:05; author: ajm65; state: Exp; lines: +9 -1
Change to skos:ConceptScheme - Reworked the definition, in line with new guide. Concept scheme now defined as 'a *description* of a set of concepts, which may include a description of relationships between those concepts'. This change made to make explicit the fact that semantic relationships between concepts may be part of a concept scheme. Also expresses modelling concept scheme as an information resource (hence the 'description' word added).
----------------------------
revision 1.33
date: 2004/12/17 13:28:08; author: ajm65; state: Exp; lines: +8 -1
Change to skos:Concept - Removed the comment about inferring the meaning of a resource of type skos:Concept, because it was misleading (move to intentional model, where properties of a concept *explain* the meaning of the concept, but do not determine it. This allows for clearer modelling of concepts in multiple schemes).
----------------------------
revision 1.32
date: 2004/12/17 13:23:26; author: ajm65; state: Exp; lines: +10 -1
Changes to skos:Collection - The word 'meaningful' added to the definition; small change to the comment to make it clearer.
----------------------------

Posted by ajmiles at 01:39 PM | Comments (0)

December 15, 2004

New Property 'hiddenLabel' added to SKOS Core

A new property skos:hiddenLabel has been added to SKOS Core. The definition for this property indicates that a hidden label is 'a lexical label for a resource that should be hidden when generating visual displays of the resource, but should still be accessible to free text search operations.'

This property is currently a sub-property of rdfs:label.

Categories SKOS Changelog
Posted by ajmiles at 08:05 PM | Comments (0)

Small change to skos:inScheme

The skos:inScheme property is no longer a sub-property of rdfs:isDefinedBy, because the latter in fact expresses more precise semantics. The latter should be used to express a relationship between a concept and its original, defining, concept scheme (if one exists). Use the skos:inScheme property expresses a relationship between a concept and any concept scheme in which it participates, which may or may not be the original, defining concept scheme.

(This change to better handle inclusion of concepts in multiple schemes).

Categories SKOS Changelog
Posted by ajmiles at 07:51 PM | Comments (0)

November 11, 2004

SKOS Core: Subject Indicators

A property with the following URI has been added to the SKOS Core Vocabulary:

http://www.w3.org/2004/02/skos/core#subjectIndicator

For a summary of this property, see:

http://www.w3.org/2004/02/skos/core/spec/#subjectIndicator

Categories SKOS Changelog

The skos:subjectIndicator property has been added to support the subject indicator mechanism for establishing the identity of a 'subject' (read 'resource' in RDF speak). This property is an inverse-functional property, allowing it to be used as a basis for resource identification.

So for example, it would quite reasonable to publish an RDF description of a concept without an assigned URI, e.g.

<rdf:RDF  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
          xmlns:skos="http://www.w3.org/2004/02/skos/core#">
  <skos:Concept>
    <skos:prefLabel xml:lang="en">Iraq</skos:prefLabel>
    <skos:subjectIndicator rdf:resource="http://psi.oasis-open.org/geolang/iso3166/#368"/>
  </skos:Concept>
</rdf:RDF>

... and then reference this concept within an RDF description of another resource using the skos:subjectIndicator property, e.g.

<rdf:RDF  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
          xmlns:skos="http://www.w3.org/2004/02/skos/core#">
  <rdf:Description rdf:about="http://www.iraqdaily.com/">
    <skos:subject rdf:parseType="Resource">
      <skos:subjectIndicator rdf:resource="http://psi.oasis-open.org/geolang/iso3166/#368"/>
    </skos:subject>
  </rdf:Description>
</rdf:RDF>
Posted by ajmiles at 12:16 PM | Comments (0)

October 22, 2004

SKOS Core: Support for Subject-Based Indexing

The following proposal for additions to SKOS Core to support subject-based
indexing has been actioned:

Add the following properties to SKOS Core:

- subject
- isSubjectOf
- primarySubject
- isPrimarySubjectOf

Additionally, the following points are a part of this proposal:

(1) skos:subject is a sub-property of dc:subject.

(2) skos:subject and skos:isSubjectOf are inverse.

(3) skos:primarySubject is a sub-property of skos:subject.

(4) skos:primarySubject and skos:isPrimarySubjectOf are inverse.

(5) Wrt skos:subject, the following rule applies:

(?d skos:subject ?x)(?x skos:broader ?y)
->
(?d skos:subject ?y)

See the SKOS Core Vocabulary Specification for an overview of these terms:

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

All new terms have an 'unstable' status and comments and suggestions are
most welcome.

Categories SKOS Changelog
Posted by ajmiles at 01:04 PM | Comments (0)

October 21, 2004

SKOS Core: Extended Support for Notes

The following properties have been added to SKOS Core:

- publicNote
- privateNote
- historyNote
- editorialNote
- changeNote

In addition, the following properties have been modified:

- definition
- example
- scopeNote

The modifications were:

(i) rdfs:domain statements removed.
(ii) Super-property statements changed.

Definitions, comments and usage examples for these properties can be viewed
via the SKOS Core Vocabulary Specification at:

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

N.B. all new note properties have an unstable status, and
comments/suggestions are welcomed.

Categories SKOS Changelog

These 8 properties constitute the set of SKOS Core note properties. They
are arranged into a property hierarchy as follow:

rdfs:comment
  skos:publicNote
    skos:definition
    skos:example
    skos:scopeNote
    skos:historyNote
  skos:privateNote
    skos:editorialNote
    skos:changeNote

N.B. None of these properties have any rdfs domain/range statements, and so
may be used to describe resources of any type.

Posted by ajmiles at 05:33 PM | Comments (0)

SKOS Core: Ordered/labelled collections of concepts

Some new vocabulary has been added to SKOS Core to support ordered/labelled collections of concepts. The primary use case for these terms is creating RDF descriptions of thesauri that have 'guide terms' and/or 'node labels'.

See the SKOS Core Vocabulary Specification for an overview of the new terms.

All new terms have an 'unstable' status, so further comments and suggestions are most welcome.

Categories SKOS Changelog

Description of the actioned proposal:

Add the following classes:

- Collection
- OrderedCollection (sub-class of Collection)
- CollectableProperty

Add the following properties:

- member (domain: Collection, range: rdf:Resource)
- memberList (domain: Collection, range: rdf:List)

To illustrate the intended usage by example, an *unordered* labelled
collection would be represented in RDF/XML as:

<rdf:RDF 
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
  xmlns:skos="http://www.w3.org/2004/02/skos/core#">
  <skos:Concept rdf:about="http://my.example.org/concept#102">
    <skos:prefLabel>Aircraft</skos:prefLabel>
    <skos:narrower>
      <skos:Collection>
        <rdfs:label>Aircraft by function</rdfs:label>
        <skos:member rdf:resource="http://my.example.org/concept#1024"/>
        <skos:member rdf:resource="http://my.example.org/concept#1026"/>
        <skos:member rdf:resource="http://my.example.org/concept#1027"/>
        <skos:member rdf:resource="http://my.example.org/concept#1028"/>
        <skos:member rdf:resource="http://my.example.org/concept#1029"/>
      </skos:Collection>
    </skos:narrower>
  </skos:Concept>
</rdf:RDF>

An *ordered*, labelled collection would be represented in RDF/XML as:

<rdf:RDF 
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
  xmlns:skos="http://www.w3.org/2004/02/skos/core#">
  <skos:Concept rdf:about="http://my.example.org/concept#56">
    <skos:prefLabel>Countries</skos:prefLabel>
    <skos:narrower>
      <skos:OrderedCollection>
        <rdfs:label>Countries by size</rdfs:label>
        <skos:memberList rdf:parseType="Collection">
          <skos:Concept rdf:about="http://my.example.org/concept#564"/>
          <skos:Concept rdf:about="http://my.example.org/concept#565"/>
          <skos:Concept rdf:about="http://my.example.org/concept#566"/>
          <skos:Concept rdf:about="http://my.example.org/concept#568"/>
          <skos:Concept rdf:about="http://my.example.org/concept#560"/>
          <skos:Concept rdf:about="http://my.example.org/concept#562"/>
        </skos:memberList>
      </skos:OrderedCollection>
    </skos:narrower>
  </skos:Concept>
</rdf:RDF>

The following points are also part of this proposal:

(1) Collections may be nested as members of other collections.

(2) Wrt 'CollectableProperty' the following rule applies:

	(?p rdf:type skos:CollectableProperty)
	(?x ?p ?c)
	(?c skos:member ?m)
	->
	(?x ?p ?m)

(3) skos:narrower is declared to be of type skos:CollectableProperty

(4) Wrt 'memberList' the following dependency rule applies:

	(?c skos:memberList ?l)
	elementOfList(?e,?l)
	->
	(?c skos:member ?e)
Posted by ajmiles at 01:46 PM | Comments (0)

October 20, 2004

SKOS Core: skos:externalID deprecated, use dc:identifier instead

The property 'skos:externalID' has been deprecated - use the Dublin Core property 'dc:identifier' instead. Categories SKOS Changelog
Posted by ajmiles at 05:39 PM | Comments (0)

SKOS Core: Definitions and examples added, comments updated

For all the current terms of the SKOS Core vocabulary, a skos:definition
property has been added, and a skos:example property has been added. The
values for the rdfs:comment properties have also been updated.

This structure is employed such that the formal definition of a term is
described by the skos:definition property, and any additional comments and
information about the term are described by rdfs:comment property(ies).

The skos:example properties point to RDF/XML files containing examples of
usage.

No SKOS Core terms are yet assigned a 'stable' status, which means that
comments and feedback on any current definitions and comments is most
welcome.

To view comments and definitions in a more user-friendly form, see the SKOS
Core Vocabulary Specification, which is generated directly from the
underlying RDF description:

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

Categories SKOS Changelog
Posted by ajmiles at 05:25 PM | Comments (0)

October 18, 2004

SKOS Core: Semantic Relation Property Extensions Moved to new 'SKOS Extensions' Vocabulary

The following SKOS Core properties have been deprecated [where the prefix
'skos' stands for 'http://www.w3.org/2004/02/skos/core#']:

skos:broaderInstantive
skos:broaderGeneric
skos:broaderPartitive
skos:narrowerInstantive
skos:narrowerGeneric
skos:narrowerPartitive
skos:relatedhasPart
skos:relatedIsPartOf

These properties are replaced by properties in the SKOS Extensions
Vocabulary namespace with the same names.

The base namespace for the SKOS Extensions vocabulary is:

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

The SKOS Extensions Vocabulary homepage is at:

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

The RDF description of the SKOS Extensions Vocabulary is at:

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

The SKOS Extensions Vocabulary Specification is at:

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

Categories SKOS Changelog
Posted by ajmiles at 06:14 PM | Comments (0)

August 27, 2004

Minor - Added Date Issued Statements

A dct:issued statement for all terms has been added, where absent, dated to the 2004-08-26 release. Categories SKOS Changelog
Posted by ajmiles at 08:33 PM | Comments (0)

August 19, 2004

SKOS Core: New property skos:hasTopConcept

A new property 'skos:hasTopConcept' has been added to the SKOS Core vocabulary. This property replaces the class skos:TopConcept, which is now deprecated.

This new property is added to support the modelling of concepts that are members of more than one scheme, and where a concept may be a top concept in one scheme and not in another.

So now, to indicate that some concept is a top concept in a specific scheme, do e.g. the following:

@prefix skos: <http://www.w3.org/2004/02/skos/core#>.
@prefix ex: <http://example.org/>.

ex:myConceptScheme  
    skos:hasTopConcept  ex:conceptA;
    skos:hasTopConcept  ex:conceptB;
    skos:hasTopConcept  ex:conceptC.
Categories SKOS Changelog

The RDF description of the new property skos:hasTopConcept is as follows:

	<rdf:Property rdf:ID="hasTopConcept">
	        <rdfs:label>has top concept</rdfs:label>
		<rdfs:domain rdf:resource="#ConceptScheme"/>
		<rdfs:range rdf:resource="#Concept"/>
	        <rdfs:comment>Use this property to indicate that a concept is a top concept in a specific concept scheme.</rdfs:comment>
		<rdfs:isDefinedBy rdf:resource="http://www.w3.org/2004/02/skos/core"/>
		<vs:term_status>testing</vs:term_status>
		<owl:versionInfo>This property replaces the deprecated skos:TopConcept class.</owl:versionInfo>
		<dct:replaces rdf:resource="#TopConcept"/>
		<dct:created>2004-08-19</dct:created>
	</rdf:Property>

The RDF description of the old class skos:TopConcept is now as follows:

	<owl:DeprecatedClass rdf:ID="TopConcept">
		<rdfs:label>Top Concept</rdfs:label>
		<rdfs:comment>A concept that sits at the top of the concept hierarchy.</rdfs:comment>
		<rdfs:isDefinedBy rdf:resource="http://www.w3.org/2004/02/skos/core"/>
		<vs:term_status>unstable</vs:term_status>
		<owl:versionInfo>This class is now deprecated.  To indicate that a concept is a top concept in a scheme, now use the skos:hasTopConcept property.</owl:versionInfo>
                <dct:isReplacedBy rdf:resource="#hasTopConcept"/>
		<dct:modified>2004-08-19</dct:modified>
	</owl:DeprecatedClass>
Posted by ajmiles at 02:20 PM | Comments (0)

August 16, 2004

SKOS Mapping Namespace Change

The SKOS Mapping RDF Vocabulary has been moved to the w3.org namespace.

The new namespace for SKOS Mapping is:

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

The HTTP link for the source RDF is:

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

This is now the permanent home for SKOS Mapping. Apologies for any
inconvenience caused.

Categories SKOS Changelog
Posted by ajmiles at 03:22 PM

August 03, 2004

Minor technical changes

Some minor mostly technical (and not design) changes to the SKOS Core vocabulary:

- the XML doctype has been changed to 'rdf:RDF'
- the entity 'vs' has been added with value the vocab status namespace
- xmlns:vs added
- dct:modified date updated
- dc:title for the schema changed to 'SKOS Core RDF Vocabulary'
- dc:contributor added for members of public-esw-thes list
- rdfs:isDefinedBy property added for each term
- the initial XML comment at the top of the file has been rewritten

Categories SKOS Changelog
Posted by ajmiles at 06:59 PM

Initial term status values added

Term status values have been added to all the terms in the SKOS Core RDF Vocabulary. The initial values are as follows:

  • ConceptScheme: testing
  • Concept: testing
  • TopConcept: unstable
  • inScheme: testing
  • prefLabel: testing
  • altLabel: testing
  • prefSymbol: testing
  • altSymbol: testing
  • externalID: unstable
  • semanticRelation: testing
  • broader: testing
  • narrower: testing
  • broaderInstantive: unstable
  • narrowerInstantive: unstable
  • broaderGeneric: unstable
  • narrowerGeneric: unstable
  • broaderPartitive: unstable
  • narrowerPartitive: unstable
  • relatedPartOf: unstable
  • relatedHasPart: unstable
  • scopeNote: testing
  • definition: testing
  • example: testing

Nothing has been given an initial value of 'stable' to allow for the rdfs:comments to be modified. (The idea is that once a term reaches a 'stable' status, it is understood that none of its properties will change further.)

Please feel free to recommend any of these terms for a 'stable' status if you feel they deserve to be so, and the rdfs:comments are satisfactory.

Categories SKOS Changelog
Posted by ajmiles at 06:38 PM