RE: [LC response] To Jeremy Carroll (JC2 on owl:real)

Hi

We will not be pursuing this point further, while remaining unconvinced of the decision

Jeremy


> -----Original Message-----
> From: Bijan Parsia [mailto:bparsia@cs.man.ac.uk]
> Sent: Monday, May 18, 2009 9:59 AM
> To: Jeremy Carroll; public-owl-comments@w3.org
> Subject: [LC response] To Jeremy Carroll (JC2 on owl:real)
> 
> Dear Jeremy,
> 
> Thank you for your comment
>      <http://lists.w3.org/Archives/Public/public-owl-comments/2009May/
> 0013.html>
> on the OWL 2 Web Ontology Language last call drafts.
> 
> To address your points in turn:
> 
> * According to a normative part of RDF Concepts,
>      <http://www.w3.org/TR/rdf-concepts/#section-Datatypes>:
> 
> "Each member of the value space may be paired with any number
> (including zero) of members of the lexical space ...
> 
> ... RDF may be used with any datatype definition that conforms to
> this abstraction, even if not defined in terms of XML Schema."
> 
> So here RDF datatypes can have an empty lexical space and a trivial
> lexical-to-value mapping, as in owl:real.
> 
> This is contradicted in RDF Semantics, <http://www.w3.org/TR/rdf-mt/
> #dtype_interp>:
> 
> "Formally, a datatype d is defined by three items:
> 
>       1. a non-empty set of character strings called the lexical
> space of d; ...."
> 
> There does not appear to be any technical reason for this prohibition
> on empty lexical spaces in RDF Semantics. For any new datatype, RDF
> systems must be upgraded to recognize which strings are ill-formed
> for that datatype. For an empty datatype, they must simply treat any
> string as ill-formed which is the desired behavior here. Thus,
> owl:real is eminently compatible with RDF systems and technically in
> compliance with one of the definitions supplied by the
> specifications. The Working Group will send an error report about
> this contradiction to the appropriate list.
> 
> * There are no negative effects from requiring the OWL 2 domain of
> discourse to be uncountable. The fundamentals of the semantics are
> unchanged; there is no need to significantly change implementations.
> 
> * The working group has discussed your document extensively and
> addressed the issues it raised. It is in fact partly in response to
> the concerns mentioned there that OWL 2 has owl:real (and
> owl:rational) as support for avoiding the problematic use of floating
> point numbers, not just for n-ary data predicates but also as a
> matter of modeling cleanliness.
> Given these considerations, the Working Group has decided to make no
> change in response to your comment.
> 
> Please acknowledge receipt of this email to <mailto:public-owl-
> comments@w3.org> (replying to this email should suffice). In your
> acknowledgment please let us know whether or not you are satisfied
> with the working group's response to your comment, and whether you
> would like us to record you as Formally Objecting to the advancement
> of OWL 2 along the W3C Recommendation Track. (Note that according to
> the W3C Process, Formal Objections are made by individuals, not
> organizations.)
> 
> Regards,
> Bijan Parsia
> on behalf of the W3C OWL Working Group

Received on Tuesday, 26 May 2009 23:55:14 UTC