Re: Datatyping

[Patrick Stickler, Nokia/Finland, (+358 40) 801 9690,]

----- Original Message ----- 
From: "ext Seth Russell" <>
To: <>
Sent: 24 September, 2002 15:43
Subject: Datatyping

> Since the WG apparently will be putting thinking caps back on regarding 
> datatyping, 

Well, I think you may be reading a bit too much into some recent 
comments on the rdf-core list. The W3C has a pretty clear process 
defined and I'm sure the WG will follow it.

Still, one significant question regarding your proposal: What if
one defines the range of the age property to be an integer. E.g.

   :age rdfs:range xsd:integer .

The triple having the lexical node will then not be valid. If you
said instead

   :age rdfs:range xsd:string .

then the triple having the typed node would not be valid.

One of the key desiderada that has been at the forefront of the
datatyping discussions is the compatability between local and
global forms of expression (or explicit and implicit forms
of expression) and global range assertions.

I'm presuming here that you intend lexical nodes to be self-denoting.



> I though I'd show the way I'd like the new datatyping to work:
> I submit the graph:
> which hopefully is consistent, yet includes the dreaded situations.
> In this graph, note the following::
> 1) There are two kinds of literal nodes:  TypedLiteral(s) and 
> LexicalNodes.  
> 2) TypedLiteral Nodes can be subjects.
> 3) LexicalNodes cannot be subjects - as in M&S.
> 4) TypedLiteral Nodes gain their semantics from the triples in the 
> graphs (not node labels).
> 5) All nodes in that graph are tidy - there are no Bnodes in that graph.
> 6) Identity is defined on all nodes.
> 7) Equality is defined on LiteralNodes but not on LexicalNodes.
> In that graph, Jenny's age is not identical to John's age, yet I would 
> like the MT to entail that equality.
> In that graph, John's age is identical to the title of movie B, yet I 
> would like the MT to entail that John's age is not equal the title of 
> movie B.  
> That graph is over on the Public-CMaps server, so anyone who is running 
> that fine graphing tool provide by UWF [1], is welcome to add to , 
> and\or correct it. The project is SemanticWeb and the name of the graph 
> is jennyAge10.
> [1]
> Seth Russell

Received on Wednesday, 25 September 2002 07:29:06 UTC