Tom,
The rdfs:Property is still available for use in OWL, and I can believe
there will be situations where it's intentionally warranted.
I agree with Schema.org's philosophy of specifying/expecting the range
settings, while agreeing to cope if the data is amiss. For example, if I
saw this:
:book1 schema:publisher "Big Publishing Inc." .
It should generally make sense to "fix" it like so:
:book1 schema:publisher _:A0 .
_:A0 rdf:type schema:Organization;
schema:name "Big Publishing Inc." .
The inverse situation may not be as simple, but it is probably also less
common.
Jeff
> -----Original Message-----
> From: DCMI Architecture Forum [mailto:[log in to unmask]]
> On Behalf Of Thomas Baker
> Sent: Monday, March 05, 2012 9:34 AM
> To: [log in to unmask]
> Subject: Re: DCAM RDF Revision revisited
>
> Hi Jeff,
>
> On Sun, Mar 04, 2012 at 11:55:49PM -0500, Jeff Young wrote:
> > > That's precisely the question I was getting at earlier in this
> thread (on
> > > Tuesday). Rephrasing...:
> > >
> > > The (current) DCAM Vocabulary Model [1] is grounded in RDFS.
> It has:
> > >
> > > -- Properties,
> >
> > Whereas RDFS allows properties to be either literals or entities,
OWL
> > makes a clear distinction:
> >
> > owl:DatatypeProperty (the range must be a literal)
> > owl:ObjectProperty (the range must be an entity)
> >
> > I doubt that I would have ever grok'd RDF without this clear
> > distinction.
>
> The problem with this is that there is some principled resistance to
> the idea
> that one _must_ neatly distinguish properties with literal ranges from
> properties with object ranges. We see this is the preference by some
> projects
> to continue using -- or even to revert to using -- the fifteen "free-
> range"
> /elements/1.1/ properties in preference to the fifteen "ranged"
/terms/
> properties [1].
>
> In the wild, I am told, well-meant range assignments often simply get
> ignored,
> whether out of simple ignorance, willful pragmatism, or out of a
> principled
> stance that the DatatypeProperty/ObjectProperty distinction forces
> "semantic
> overcommitment". If were to happen on a wide scale (maybe someone
here
> can
> point to some numbers?), then it is consumers of Linked Data who would
> need to
> adjust.
>
> The Schema.org initiative, in my understanding, follows an (implicit?)
> policy
> of defining ranges with precision, but in the expectation that those
> ranges
> may, in practice, be ignored. If I have understood correctly, this
> seems wise.
>
> Tom
>
> [1] http://wiki.dublincore.org/index.php/FAQ/DC_and_DCTERMS_Namespaces
>
> --
> Tom Baker <[log in to unmask]>
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