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Re: [OEP] OWL and Semantic interoperability $swbpd

From: Deborah L. McGuinness <dlm@ksl.stanford.edu>
Date: Mon, 07 Feb 2005 09:59:35 -0800
Message-ID: <4207AC87.8060206@ksl.stanford.edu>
To: "Uschold, Michael F" <michael.f.uschold@boeing.com>
CC: Jim Hendler <hendler@cs.umd.edu>, public-swbp-wg@w3.org, "Jones, David H" <david.h.jones@boeing.com>
a couple of points that come out for me from the thread so far:

1 - i am also reactive to the feeling that is left from the note that 
owl is inferior.  
i find its expressive power to be superior to other things that people 
have tried to use for semantic interoperability in at least the database 
world.
2 - we might try to keep subjective words like inferior out of the note
3 - i think it is clear that we need to be precise with what 
definition(s) we are considering for semantic interoperability
4 - if we are using a kind of mapping as a definition, i like think one 
of the strong claims of owl (and all description logics)
is that they can be used to express  necessary conditions for membership 
in a class, and
necessary and sufficient conditions for membership in a class,
and then provide subsumption and recognition reasoners to identify when 
classes are subclasses of other and to identify when
instances are members of a class.
Additionally, OWL provides convenient ways to make equivalence 
statements that can be used to facilitate mappings.
(additionally it provides convenient ways to make different from 
statements.)

one can look at history and go back to the prose family of configurators 
that used an early DL - CLASSIC - and could have been viewed to be 
solving semantic interoperability problems since it interfaced with 
dozens of databases.

Deborah

Uschold, Michael F wrote:

>Thanks Jim for your input.
>
>More concrete dicussion can take place when the note has some meat on it
>for you and others to assess. However, I can respond to some of your
>points.
>See [MFU] below. 
>
>
>-----Original Message-----
>From: Jim Hendler [mailto:hendler@cs.umd.edu] 
>Sent: Sunday, February 06, 2005 2:29 PM
>To: Uschold, Michael F
>Cc: public-swbp-wg@w3.org
>Subject: Re: [OEP] OWL and Semantic interoperability
>
>for the note is:
>  
>
>>This note addresses the role of OWL in overcoming problems of semantic
>>heterogeneity.  We briefly characterize what we mean by semantic
>>interoperability, and what the challenges are. We describe some OWL
>>constructs that are designed to support semantic interoperability and
>>illustrate them with examples. We highlight their strengths and
>>limitations.  The main message is that OWL is no silver bullet for the
>>general problem of achieving semantic interoperability.  The support
>>provided is very limited.  Many of these limitations will be overcome
>>    
>>
>by
>  
>
>>the Semantic Web Rule Language (SWRL) that is currently under
>>development.
>>    
>>
>
>Mike - let me put this in a friendly way -- I don't like this at all. 
>First of all, when you compare OWL to any of the alternatives it is 
>way better - 
>[MFU] 
>Which alternatives to OWL is OWL superior to? In what way? Perhaps you
>have something different in mind by 'semantic interoperability' than I
>do.
>
>When I compare OWL to alternatives (such as CWM or SWRL, and perhaps
>FLogic) for providing semantic interoperability , OWL comes up short
>(see below).
>==
>
>If you stopped after the sentence "OWL is no silver 
>bullet ..." I'd be fine.  However, you go on to say "the support 
>provided is very limited" which I don't agree with, and which also is 
>a subjective statement at best.  
>
>[MFU] By limited, I meant it cannot support some extremely simple and
>minor things that are critical to many real world interoperability
>scenarios. e.g.  doing arithmetic to convert between different units
>(e.g. feet/meters). One can do this very easily using CWM, and SWRL.
>That assertion is not subjective. Going from this fact to an
>interpretation that OWL is "very limited" is open to discussion, and
>perhaps should be re-worded for different emphasis. For example: "OWL
>provides x,y and z to support interoperability. a,b,and c are not
>supported by OWL. The extent to which this is a limitation depends on
>the nature of one's application." would probably be better. In the
>experience of myself and some of my colleagues, OWL's support for
>interoperability is indeed very limited. Without simple arithmetic and
>rules, most of what we need is not supported. 
>
>I would be very grateful if you [Jim or anyone] could give some examples
>of non-toy real-world problems of interoperability that can be solved
>with ONLY the support that OWL provides. That would be a good way to
>start off on a postive note; and then move on to some of the
>limitations, concluding that OWL is no silver bullet, and that some kind
>of rule language is needed to perform interoperability beyond what OWL
>currently gives.
>
>===
>
>I would even further object to the 
>last sentence - first, SWRL has no official status and may not even 
>be the eventual choice for a standard, second SWRL has not been 
>tested in interoperability issues, and it is unclear to me why more 
>expressivity should increase the ability to do reuse -- if anything I 
>would actually expect the reverse in practice...
>[MFU] I mean to say that more expressivity increases the ability to
>express and execute mappings between one ontology and another for the
>purpose of interoperability. I'm not making any claims about reuse.
>
>===
>  So let's keep this factual and focused, and leave the hypotheticals 
>out of WG notes
>[MFU] That is my intent. I will rely on you and others to identify
>hypothethicals that may unintentionally find their way into the note.
>===
>  -JH
>p.s. And in case anyone is interested, I would like to deny in the 
>strongest possible terms that "The support provided (for 
>interoperability) in OWL is very limited",  the URI/RDF basis of OWL 
>makes the sharing of terms possible in a way that no KR langauge in 
>the past has ever had, and is a good part of the reason that OWL is 
>now the most used KR langauge in the history of AI.
>
>[MFU] Again, I'm not making claims about reuse and sharing, per se. What
>do you see as the relationship/connection between reuse/sharing and
>interoperability?  This note does not focus on reuse/sharing per se. It
>is no doubt part of the bigger picture of semantic interoperability that
>I should perhaps explore more. 
>
>As I read and reread your comments, it seems likely that we have two
>fairly different things in mind by 'semantic interoperability'. What do
>YOU have in mind?  Perhaps when you think of semantic interoperability,
>you are mainly thinking of the reuse and sharing of ontologies and
>ontology terms using the URI/RDF basis?  Perhaps THIS is what you see as
>being superior to all the alternatives? On that we can agree.
>
>The way that OWL is inferior, is in its abilty to express mappings
>between ontologies to that applications using different ontologies can
>interoperate. This is what I mean by semantic interoperability. 
>===
>
>
>
>
>Professor James Hendler			  Director, Semantic Web and 
>Agent Technologies
>Maryland Information and Network Dynamics Lab.	  301-405-2696
>8400 Baltimore Ave, Suite 200			  301-314-9734 (Fax)
>College Park, MD 20742
>http://www.cs.umd.edu/users/hendler
>
>  
>

-- 
 Deborah L. McGuinness 
 Co-Director Knowledge Systems Laboratory 
 Gates Computer Science Building, 2A Room 241 
 Stanford University, Stanford, CA 94305-9020 
 email: dlm@ksl.stanford.edu
 URL: http://ksl.stanford.edu/people/dlm
 (voice) 650 723 9770    (stanford fax) 650 725 5850   
Received on Monday, 7 February 2005 18:00:15 GMT

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