Re: Extending RDFS, property-classes

Hello Jiri,

The OWL 2 Specification, now in last call, has extended facilities for
annotation. You might want to have a look..

The relevant sections are in the Syntax specification and the RDF Mapping.

http://www.w3.org/TR/2008/WD-owl2-syntax-20081202/#Annotations
http://www.w3.org/TR/2008/WD-owl2-mapping-to-rdf-20081202/#Translation_of_Annotations

If you aren't familiar with functional syntax for OWL (it's relatively
new) the thing to know is that it gives a more concise way to write
OWL statements but is mapped to RDF/XML for exchange. We do intend to
enhance that document so the examples are in RDF as well, but it is
work in progress.

Briefly the facility allows for annotation of any entity, including
axioms such those a simple triple might encode - called a
PropertyAssertion in the syntax document, but also ones that have a
more complex RDF encoding, such as an OWL restriction or to annotate
an annotation itself.

Even if you are not using much OWL in your application, you could use
the OWL vocabulary and mapping and vocabulary to write your
annotations.

Regards,
Alan

On Mon, Feb 9, 2009 at 3:54 PM, Jiri Prochazka <ojirio@gmail.com> wrote:
> Hi,
> inspired with recent discussion with Richard Newman ("RDF vocabulary
> scope guidelines, promoting properties to classes  - property
> identifiers") I have a suggestion to make.
>
> RDF has no way of identifying predicate (property) uses (triples), which
> only restricts information about them to:
> 1) about what they state something (domain)
> 2) what they state about something (range)
>
> This is insufficient for number of uses, take for example Richards tag
> ontology: http://www.holygoat.co.uk/projects/tags/
>
> Apart from properties tag:taggedWithTag and tag:isTagOf, it defines
> class tag:Tagging, which extends them (it is these properties promoted
> to class), allowing more information about the relation to be expressed.
>
> This is a good thing, but unfortunately there is no link between the
> properties and the class, which makes the data tagged with the
> properties and the data tagged with the class, like they each used
> different non-interlinked vocabularies...
>
> I suggest to develop an extension to the vocabulary describing
> vocabularies (RDFS, OWL), so vocabulary designers could specify the link
>  and inferencing engines could work with it...
>
> The vocabulary should map the property to the property-class since the
> expressiveness of the property is subset of the one of the property-class.
>
> Basically the vocabulary draft should be:
>
> :isPromotedProperty a rdf:Property ;
>        rdfs:domain rdfs:Class ;
>        rdfs:range rdf:Property .
> # But also it should use it's own philosophy on itself:
> :PropertyPromotion a rdfs:Class ;
>        rdfs:subClassOf rdf:Property .   (really not sure here)
> :promotionOf a rdf:Property ;
>        rdfs:domain :PropertyPromotion ;
>        rdfs:range rdf:Property .
> :hasDomain a rdf:Property ;
>        rdfs:subPropertyOf rdfs:domain ;   (really not sure here)
>        rdfs:domain :PropertyPromotion .
> :hasRange a rdf:Property ;
>        rdfs:subPropertyOf rdfs:range ;   (really not sure here)
>        rdfs:domain :PropertyPromotion .
> # And final craziness:
> :PropertyPromotion a :PropertyPromotion ;
>        :promotionOf :isPromotedProperty ;
>        :hasDomain rdfs:Class ;
>        :hasRange rdf:Property .
> :PropertyPromotion :isPromotedProperty :isPromotedProperty .
>
> Important is that the conversion can be done both directions.
>
> Please comment on this proposal.
> If at least some people think this is a good idea, I could work on the
> vocabulary and rdfs:label and rdfs:comment it and publish it, however in
> corner of my mind I think it would need backing of W3C to be of any use
> (as all vocabulary describing vocabularies).
>
> Kind regards,
> Jiri Prochazka
>
>

Received on Monday, 9 February 2009 22:39:36 UTC