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Re: ACTION-274: first draft

From: Ivan Herman <ivan@w3.org>
Date: Thu, 29 Jan 2009 14:57:35 +0100
Message-ID: <4981B5CF.6030002@w3.org>
To: Bijan Parsia <bparsia@cs.man.ac.uk>
CC: W3C OWL Working Group <public-owl-wg@w3.org>
Just immediate comments, there might be more. Sorry if some of those are
a bit vague...

- I am a bit afraid that the response is too long. I cannot put my
finger on it where exactly, but we should see if we could cut it. The
current response may very well lead to a long and possibly endless
discussion which would benefit nobody.

- I am not sure that 'personalizing' the comment is a good idea. The
comment is signed by Jeremy in his capacity as TQ AC rep, so his
presence on the group in its earlier self may not be appropriate. I am
also not sure the referring to persons, like Stefan's, is appropriate.

- One specific comment in TQ text is:

[[[
Since almost all TopQuadrant's business uses both RDF and OWL together
the implicit requirement in OWL 1.0 that OWL and RDF should work well
together, remains a critical requirement for OWL2. We do not see this
listed as a requirement, and believe that several of the new features
added are in practice in conflict with this requirement.
]]]

I think we should first acknowledge that the current set of document
needs a number of editorial improvements to make it clear that the
relationship between OWL 2 and RDF is the same as for OWL 1 and RDF. We
should also emphasize that the RDF Full semantics is in the making,
although not yet in LC; however, when finished, it will have an equal
weight to the direct semantics. The fact that RDF is _the_ exchange is
also a fact worth emphasizing in this context.

I actually believe that we should _not_ rush in sending this response
back to TQ. There is no reason to do so. The reason I am thinking is
that, while working through the other comments, we might (hopefully we
will!) take a number of resolutions that we can refer to (eg, in the
area of RDF-OWL relationships). That could make the response more factual.

Just my 2 cents...

Ivan

Bijan Parsia wrote:
> 
> http://www.w3.org/2007/OWL/wiki/LC_Responses/JC1
> 
> I've mostly completed a very preliminary draft of a reply to TQ. It's
> long. It could be longer. It could be shorter and contain more content.
> 
> One thing I could do is write up my dissection of the story into the
> wiki and we can point to that.
> 
> Cheers,
> 
> Bijan.
> 
> -----------------------
> 
> Dear Jeremy,
> 
> Thank you for your comment:
>       
> <http://lists.w3.org/Archives/Public/public-owl-comments/2009Jan/0051.html>
> on the OWL 2 Web Ontology Language last call drafts.
> 
> The comment you've sent is quite long and complex which attempts to
> present quite a deep understanding of TopQuadrant's perspective. The
> working group appreciates that effort and is equally committed to the
> consensus process. This response is to what we understand as the
> broadest action we believe you request of us. Where we discerned
> smaller, specific technical issues that could be sensibly dealt with
> separately, we separated them out. You will receive distinct responses
> for each of those.
> 
> We believe that the fundamental comment and call for action is the
> following quote:
> 
>   """We ask that many under-motivated new features should be dropped,
> including all unmotivated new features."""
> We perceive the rest of the text as explication of the general approach
> you would like the group to take when assessing when a feature is under-
> or un-motivated along with a set of examples of where TopQuadrant would
> judge a feature to be under- or un-motivated.
> 
> We distinguish two sorts of judgement: A feature may be under- or
> un-motivated with respect to TopQuadrant's perception of its current and
> likely business needs (and of its customer base), and under- or
> un-motived with respect to a broad enough community (esp. of W3C
> members) to be worth standardization, all things considered (including
> potential asymmetric costs to TopQuadrant or to other parties). We
> believe that is is the latter that is our responsibility to determine to
> the best of our abilities, though, obviously the former is critical
> input to those judgments. Essentially, the consensus process is for the
> WG to take TopQuadrant's input very seriously and to point TopQuadrant
> to evidence of other parties' interests. Hopefully, we can reach
> consensus. We welcome ongoing feedback from TopQuadrant.
> 
> One point of clarification: While we are happy to take your feedback on
> the LC drafts via comments on the FPWD of the New Features &
> Rationales(NF&R) document, we wish to point out that since the NF&R
> document is not complete, there may be significant distortions in your
> understanding of the motivations, costs, and benefits of the design of
> OWL2. The working group is satisfied that it did weight the costs and
> benefits broadly and often made decisions based on minimizing the costs
> and maximizing the benefits to organizations like your own, often based
> on feedback from you, Jeremy, personally (which was much appreciated).
> Thus, we do not think there is sufficient justification to do a
> systematic re-review of each feature.
> 
> In particular, you claim that "The rationale document (and the design)
> has not taken into account the cost of new features particularly to
> those who do not need them" (I focus on the design issue. The rationale
> document will be, in due course, updated.) If we examine your
> illustrative story, we note that is clear that this story could equally
> well function without OWL 2. For example, one could replace OWL2
> throughout with OWL DL and OWL Full and OWL1 with OWL Lite. For syntax,
> one could have ontologies published in Turtle, NTriples, Manchester
> Syntax, etc. Furthermore, one could point to extensions like Protege's
> extensions for QCRs and user defined datatypes and, for that matter, OWL
> 1.1 and even current versions of OWL.
> 
> Thus, we do not believe that the story gives new information or a new
> perspective. One of the goals of OWL 2 from the beginning was to reduce
> or eliminate, as much as possible, these costs by producing a standard
> new version to converge on. We believe the overall advantages and,
> especially, the new clarity of the specification will make it easier for
> tool developers to cope with real world ontologies and for new tool
> developers to enter the market. Furthermore, the working group has
> continually worked to mitigate the transition costs as much as possible.
> OWL2 deliberately avoid radical new features (such as non-monotonic
> features, or an entirely new, stratified metamodeling system, or fuzzy
> extensions). Even features that are well understood and have strong
> utility and demand were dropped or weakened in response to the sorts of
> analyses you ask for, e.g., property punning or required n-ary data
> predicates.
> 
> While the working group might have erred in some of this, we do not
> believe that we can make a more accurate prediction at this time, nor do
> we believe that we did not successfully analyze matters along the way.
> 
> Regarding bias, we first point out that the working group has had
> members strongly representing the point of view you advocate, including
> yourself. If you believe that your interests and comments were not
> given, procedurally, due consideration, then we encourage you to raise
> an issue with W3C management.
> 
> Secondly, members of the working group who might possibly be seen to
> have the sort of bias you are concerned about are precisely the people
> who have striven to solicit negative cost analyses. For example, the
> panel "An OWL Too Far" was proposed by Peter, Ian, Uli, and myself and
> included Stefan Decker, a long time opponent of OWL DL and, indeed, OWL.
> (Stefan has not been participating in the OWL 1.1 to 2 effort, so this
> was a deliberate attempt to bring in a competing voice that had "given
> up".)
> 
> Again, the working group, as a collective, could be wrong. Time will
> tell. But we do not think there is more that we could have done to avoid
> the problems in methodology that you site. At this point, we just have a
> difference of opinion.
> 
> And not a large one, as far as we can tell. TopQuadrant endorses many of
> the features. The working group believes that they will come to endorse
> more. There are many features, like property chains, that have been
> opposed by some people as unmotivated who are now enthusiastic about them.
> 
> Furthermore, at the moment we have strong evidence from last call of
> wide endorsement of the overall design.@@pointers to last call comments
> 
> @@Something about HCLS?!?
> 
> Finally, we believe that fundamentally reassessing a large number of
> features -- and even dropping them -- has considerable costs of their
> own. In general, there hasn't been strong opposition to the feature set
> and quite a bit of support. Changing that risks breaking the
> considerable consensus we already have. Without specific evidence of
> issues, we do not believe that it is sensible, or cost effective, to
> risk breaking that consensus.
> 
> As for your other proposal, that we brand the features "Web-SHROIQ". We
> are rather confused... severing any connection to OWL seems to introduce
> potentially even more confusion (there's yet another ontology
> language?). Given the near total overlap between OWL1 and OWL2 (the
> overwhelming majority of the language is the same; OWL1 ontologies are
> OWL2 ontologies) while it would certainly make it easier for people who
> strictly don't need OWL2 features to ignore it, it would also make it
> exceedingly difficult for everyone else as well as muddling the message.
> It is also outside the scope of our charter.
> 
> Please acknowledge receipt of this email and let us know whether or not
> you are satisfied with the working group's response to your comment.
> 
> Regards,
> Bijan Parsia
> on behalf of the W3C OWL Working Group
> 

-- 

Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf


Received on Thursday, 29 January 2009 13:58:10 GMT

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