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RE: [URW3 public] Re: [URW3] ... three questions based on the last telecon

From: Giorgos Stoilos <gstoil@image.ece.ntua.gr>
Date: Wed, 18 Jul 2007 20:47:39 +0300
Message-Id: <200707181747.l6IHlVk6022478@manolito.image.ece.ntua.gr>
To: "'Umberto Straccia'" <umberto.straccia@isti.cnr.it>, <public-xg-urw3@w3.org>



> -----Original Message-----
> From: public-xg-urw3-request@w3.org [mailto:public-xg-urw3-request@w3.org]
> On Behalf Of Umberto Straccia
> Sent: Wednesday, July 18, 2007 3:57 PM
> To: public-xg-urw3@w3.org
> Subject: Re: [URW3 public] Re: [URW3] ... three questions based on the
> last telecon
> 
> 
> On Jul 18, 2007, at 2:09 PM, Ken Laskey wrote:
> 
> >
> > Peter,
> >
> > Again the question is what is the purpose of our uncertainty ontology.
> 
> The OWL ontology can be used to describe different types of
> uncertainty, but can also to used to describe HOW uncertain
> information is represented in OWL (without any language extension) or
> RDF/RDFS.
> 
> To be explicit, suppose I would like to express the concept of YOUNG
> using an explicit fuzzy membership function such as a left-shoulder
> function with parameter a=20, b=30 (below 20 someone is young to
> degree 1, after 30 he is young to degree 0, in between we use linear
> interpolation).
> 
> Now, we have two options
> 
> a) either we suggest an extension to OWL (more precisely OWL-DL) or
> RDF/RDFS to explicitly accommodate such functions (i.e. we propose a
> language construct for that)
> b) or we develop an OWL-DL ontology (or RDF/RDFS ontology) describing
> HOW to represent such information into the current standardized OWL-
> DL language. In our specific case, we may say that
> 
> LeftShoulderFunction ISA FuzzyMembershipFunction
> 			 WITH HasParameterA of type Float
> 			 WITH HasParameterB of type Float
> 
> 
> Then we can represent Young with
> 
> Young ISA VagueConcept
> 	  WITH HasFuzzyMembershipFunction of type LeftShoulderFunction WITH
> HasParameterA = 20
> 								       WITH
HasParameterB
> = 30
> 
> It is then up to a parser to correctly interpret the statements and
> then to load them into an underlying reasoning system.
> 
> In this way our objective is (using the use cases) to develop an
> ontology, which describes HOW different notions of imperfect
> knowledge is represented in OWL-DL (RDF/RDFS).
> 
> 	-Umberto.

I think your example nicely differentiates between the two issues you
identify; an ontology about uncertainty types and an ontology about the
ingredients of uncertainty. 

But I hope that you do not propose such a way for actually capturing
uncertainty. I think such a way would create interoperability issues. So
anyone can use OWL and give to the above properties different names or use
different ways to capture the same meaning. So one would require to agree
upon a common way or common names which finally might boil down to some new
syntactical elements, i.e. a language extension.

-gstoil

> 
> 
> 
> > I believe the properties you propose may be important as part of
> > our conclusions of what information an _instance_ must eventually
> > convey, but is it necessary in our ontology if we are using that as
> > a guide for classifying descriptive aspects of uncertainty?
> >
> > As I note in an email I just sent on criteria for proposing OWL
> > extensions, examples of how something would be used are encouraged.
> 
> 
Received on Wednesday, 18 July 2007 17:47:42 GMT

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