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Re: Datatyping Summary V4

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Mon, 04 Feb 2002 16:10:24 +0200
To: ext Brian McBride <bwm@hplb.hpl.hp.com>, RDF Core <w3c-rdfcore-wg@w3.org>
Message-ID: <B88462F0.D197%patrick.stickler@nokia.com>
On 2002-02-04 15:00, "ext Brian McBride" <bwm@hplb.hpl.hp.com> wrote:


> Issue B10: Say what you mean
> ============================
> 
> status: ?
> 
> The concern here is that in TDL, a literal denotes a pair consisting of a
> value and a lexical representation of that value.  The problem is then that
> the german representation of floating point number, e.g. "10,5" is
> different from the english representation, e.g. "10.5".
> 
> Thus under TDL a german 10 and a half is a different thing from an english
> 10 and a half.
> 
> 
> More formally, under TDL:
> 
>  <foo>      <eg:size>   _:s1 .
>  _:s1       <rdf:value> "10,5" .
>  _:s1       <rdf:type>  <xsd:double-de> .
> 
>  <bar>      <eg:size>   _:s2 .
>  _:s2       <rdf:value> "10.5" .
>  _:s2       <rdf:type>  <xsd:double> .
> 
> does not entail:
> 
>  <foo> <eg:size> _:s .
>  <bar> <eg:size> _:s .

Firstly, I presume you meant

  <foo> <eg:size> _:s2 .
  <bar> <eg:size> _:s1 .

> Does anyone dispute the facts,

I don't think so.

> or that this is a significant issue?

But, this simply has to do with different datatypes and one would
expect that different datatypes will define different lexical spaces.

If we want to change the definition of what a datatype is, so
that we can define a single value space with multiple disjunct
lexical spaces, fine. But at present, that's not the definition
of a datatype. A datatype has a single lexical space.

This also falls in to the general category of "different ways
to say the same thing" which includes synonymous vocabularies
(MARC, ONIX, PRISM, DC, and countless proprietary ones) or
whether (xsd:integer, "5.0") is the same as (xsd:integer, "5.000").

My question is, how can you know that the above entailment
holds even for the S treatment?

I think there is some confusion here between
the above case, using S-P involving two bNodes (for which
I don't think this was really an issue) and the following case
involving a single bNode using the S-A idiom

   <foo>      <eg:size>   _:s1 .
   _:s1       <xsd:double-de>  "10,5" .
   _:s1       <xsd:double>  "10.5" .

where we know that _:s1 denotes a member of the value spaces
of both xsd:double and xsd:double-de because of the shared node.

But even with the S-A idiom, if we have

   <foo>      <eg:size>   _:s1 .
   _:s1       <xsd:double-de>  "10,5" .

   <bar>      <eg:size>   _:s2 .
   _:s2       <xsd:double>  "10.5" .

this also does not entail

   <foo> <eg:size> _:s2 .
   <bar> <eg:size> _:s1 .

So, the significance of this issue is unclear in several ways...
(at least to me ;-)

Cheers,

Patrick

--
               
Patrick Stickler              Phone: +358 50 483 9453
Senior Research Scientist     Fax:   +358 7180 35409
Nokia Research Center         Email: patrick.stickler@nokia.com
Received on Monday, 4 February 2002 09:09:17 EST

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