- From: Ivan Herman <ivan@w3.org>
- Date: Thu, 29 Jan 2009 14:57:35 +0100
- To: Bijan Parsia <bparsia@cs.man.ac.uk>
- CC: W3C OWL Working Group <public-owl-wg@w3.org>
- Message-ID: <4981B5CF.6030002@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 UTC