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Re: Denotation of datatype values

From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
Date: Fri, 12 Apr 2002 11:33:32 +0100
Message-Id: <5.1.0.14.2.20020412111934.03b23890@joy.songbird.com>
To: Patrick Stickler <patrick.stickler@nokia.com>
Cc: Jeremy Carroll <jjc@hplb.hpl.hp.com>, RDF Core <w3c-rdfcore-wg@w3.org>
Er, do we have a disconnect here?

Pat, if you're following this:  I note your document that was at 
<http://www.coginst.uwf.edu/users/phayes/simpledatatype23-02-2002.html> is 
no longer there.  Has it been moved?  It would be good if it were kept 
available for a while, since that seems to be our last published point of 
consensus.

Anyway, to resume normal programming...

At 09:53 AM 4/12/02 +0300, Patrick Stickler wrote:
>On 2002-04-11 18:53, "ext Graham Klyne" <Graham.Klyne@MIMEsweeper.com>
>wrote:
>
> > At 12:22 PM 4/11/02 +0200, Jeremy Carroll wrote:
> >> Now we add the range constraint on <age>
> >>
> >> <Jane> <age> "25" .
> >> <film> <title> "25" .
> >> <title> <range> <xsd:string> .
> >> <age> <range> <xsd:integer> .
> >>
> >> We now have the film's title delivered as <xsd:string,"25"> the 
> woman's age
> >> delivered as <xsd:integer,"25"> and they are different.
> >> Hence we see defeasible reasoning: in the light of new information we 
> revise
> >> our knowledge that Jane's age is <xsd:string,"25">, which in turn 
> causes us
> >> to revise our conclusion that Jane's age and the film's title are the 
> same.
> >
> > My understanding of PatH's last proposal is that this graph is not
> > satisfiable.  More precisely:
> >
> > [[[
> > <Jane> <age> "25" .
> > <age> <range> <xsd:integer> .
> > ]]]
> >
> > is not satisfiable because "25" denotes a string and <xsd:integer> does not
> > contain strings in its class extension.
>
>This is true if <range> equates to rdfs:range. I presumed it
>equated to rdfd:range, in which case, there is no problem.
>
>It really will help, Jeremy, if you use the precise vocabulary
>that we have come up with, especially if commenting on the current
>WD, otherwise, we have no basis for mutual understanding. I know
>that to some extent, you are trying not to beg the question by
>keeping some terms somewhat ambiguous, but it makes it too hard
>to know exactly what you mean. If you mean rdfs:range, please say so.
>If you mean rdfd:range, again, just say so. etc. OK?

Ummm... if you mean to interpret <range> as <rdfd:range>, then according to 
something Pat said a while ago [1], that has _no effect at all_ on the 
denotation of anything.  That simply describes a syntactic constraint on 
literal labels in the RDF graph (which are satisfied by the above examples 
so can be dropped without having any any further effect on the semantics).

#g
--

[1] http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Mar/0241.html :

[[
Right. The point is that rdfs:drange (or whatever we call it) really
says nothing about the actual range: it ONLY invokes datatype
checking. Now, one might reasonably expect that the actual range was
'in line' with the datatype checking, but that could be
]]

[[
 >According to section 5 of [1], taking account that literals denote
 >themselves, this means that
 >
 >    <x,y> in IEXT(I(ex:age)) => z=L2V(I(datatype:decimal))(y) for some z

No, it doesn't constrain the relational extension. What it does say is that

( <x,y> in IEXT(I(ex:age))  AND  y a literal)  =>
z=L2V(I(datatype:decimal))(y) for some z

ie IF its a literal then its in the lexical space of
datatype:decimal. But if its not, then nothing particular follows.
]]




-------------------
Graham Klyne
<GK@NineByNine.org>
Received on Friday, 12 April 2002 06:32:54 EDT

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