W3C home > Mailing lists > Public > public-xg-urw3@w3.org > July 2007

Re: [URW3 public] OWL extensions [was Re: [URW3] ... three questions based on the last telecon]

From: Umberto Straccia <umberto.straccia@isti.cnr.it>
Date: Thu, 19 Jul 2007 14:36:09 +0200
To: public-xg-urw3@w3.org
Message-id: <3585CE2F-D57C-41E0-897F-765C2BC3E4BC@isti.cnr.it>


On Jul 19, 2007, at 10:22 AM, Trevor Martin wrote:

> This is precisely the choice faced by implementers of logic  
> programming + uncertainty languages .... you can extend the  
> language and the inference mechanism or express and process the  
> uncertainty within the standard language.
>
> tall(John) : 0.7
>
> vs
>
> tall(John, 0.7)
>
> (... in both cases, without saying what 0.7 represents)
>
> The former approach gives you more control, reduces to "standard"  
> notation when the uncertainty is omitted and (I think) makes the  
> semantics clearer;
> the latter involves no change to existing notation (hence is easier  
> to  sell ) but gets messy when only some of the representation  
> requires the uncertainty and obscures the meaning of the annotation.
>

Not exactly, Trevor.  What should be a minimal setting (you know that  
there are 200+ citations about Logic Programming, uncertainty/ 
vagueness ....) be ? What semantics?

Even an expression of the form

P(c1, ...cn): 0.7

is open to a pletora of semantic options ...

What I say is is that

> tall(John) : 0.7

should rather be represented like (guided by the uncertainty ontology)

sentence s IS tall(John) AND s HasTruthDegree = 0.7

Anyway, that's just my opinion ...
Received on Thursday, 19 July 2007 12:31:21 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 30 April 2008 09:52:44 GMT