Section: Describing a Concept Scheme

To describe the basic properties of a concept scheme, do for example the following:

<rdf:RDF  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
          xmlns:skos="http://www.w3.org/2004/02/skos/core#"
          xmlns:dc="http://purl.org/dc/elements/1.1/"
          xmlns:foaf="http://xmlns.com/foaf/0.1/">
         
  <skos:ConceptScheme rdf:about="http://my.example.org/thesaurus">
    <dc:title xml:lang="en">My Example Thesaurus</dc:title>
    <dc:description xml:lang="en">An example thesaurus invented for the SKOS Core guide.</dc:description>
    <!-- Unqualified-style use of Dublin Core: -->
    <dc:creator>Alistair Miles</dc:creator>
    <!-- Qualified-style use of Dublin Core with FOAF: -->
    <dc:creator>
      <foaf:Person>
        <foaf:name>Alistair Miles</foaf:name>
        <foaf:mbox rdf:resource="mailto:a.j.miles@rl.ac.uk"/>
      </foaf:Person>
    </dc:creator>
    <dc:rights xml:lang="en">Copyright Â© 2004 Alistair Miles. All rights reserved.</dc:rights>
  </skos:ConceptScheme>

</rdf:RDF>

Note that in the example above, Dublin Core properties have been used. In fact any properties from any RDF vocabulary may be used in a description of a concept scheme ... this is the nature of RDF. However, it is generally a good idea to use properties from well-established vocabularies, wherever possible.

Both the Dublin Core element set [ref] and the Dublin Core terms vocabulary [ref] have a number of properties suitable for describing the basic properties of a concept scheme (e.g. dc:publisher, dcterms:audience, dcterms:issued etc.)

If your concept scheme has some structure (i.e. is not just a flat list of concepts) then the top level concepts in the scheme should be identified within the description of the concept scheme. The top level concepts are the concepts that sit at the top of the broader/narrower hierarchies. This means extending the description of the concept scheme to include, for example, the following:

<rdf:RDF  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
          xmlns:skos="http://www.w3.org/2004/02/skos/core#"
          xmlns:dc="http://purl.org/dc/elements/1.1/"
          xmlns:foaf="http://xmlns.com/foaf/0.1/">
         
  <skos:ConceptScheme rdf:about="http://my.example.org/thesaurus">
    <!-- Other properties of the concept scheme ... -->
    <skos:hasTopConcept rdf:resource="http://my.example.org/thesaurus/activities#concept"/>
    <skos:hasTopConcept rdf:resource="http://my.example.org/thesaurus/processes#concept"/>
    <skos:hasTopConcept rdf:resource="http://my.example.org/thesaurus/objects#concept"/>
    <skos:hasTopConcept rdf:resource="http://my.example.org/thesaurus/periods#concept"/>
    <skos:hasTopConcept rdf:resource="http://my.example.org/thesaurus/materials#concept"/>
  </skos:ConceptScheme>

</rdf:RDF>

Once you have identified and described your concept scheme, you will want to include an extra statement in the description of each of your concepts:

<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/thesaurus/materials#concept">
    <!-- Other properties of the concept ... -->
    <skos:inScheme rdf:resource="http://my.example.org/thesaurus"/>
  </skos:Concept>

</rdf:RDF>

This extra statement expresses the fact that the concept is a part of the given concept scheme.

End section'

Prior text:

Early notes from AJM>

-- What is a concept scheme? (Includes thesauri, terminologies, glossaries ...)

-- How to choose a URI for your concept scheme ...

Include in this section recommendations for how to choose the URI for your concept scheme, with considerations based on what that URI should resolve to.

-- What properties to use in describing a concept scheme, e.g. DC, others? ...

If the description of a concept scheme is to include statements about where all the scheme's statements should be loaded from, what properties do we use for that? (i.e. how do we say 'concept scheme X consists of the statements from the model which can be downloaded from the URL y ...)

-- RDF+XML example of concept scheme description