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

From: Trevor Martin <Trevor.Martin@bristol.ac.uk>
Date: Fri, 20 Jul 2007 09:04:14 +0100
Message-Id: <03522A5E-16A8-4A34-BDED-8E65258DB1C7@bris.ac.uk>
To: public-xg-urw3@w3.org


On 19 Jul 2007, at 13:36, Umberto Straccia wrote:

>
>
> 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?

I was trying to avoid (for the time being) the question of what the  
number (or annotation) means
>
> 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 ...
>
>

I think this is the second option I mentioned - effectively you say   
R1(X, Y) AND  R2(X, Z)  where X =  sentence s, R2 = HasTruthDegree, etc

This doesn't give any special status to HasTruthDegree.

I'm not disagreeing, just trying to clarify things in my own mind ....

Trevor


>
>
>
Received on Friday, 20 July 2007 08:03:35 GMT

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