- From: Ivan Herman <ivan@w3.org>
- Date: Wed, 11 Feb 2009 12:02:20 +0100
- To: Ian Horrocks <ian.horrocks@comlab.ox.ac.uk>
- CC: Mike Smith <msmith@clarkparsia.com>, W3C OWL Working Group <public-owl-wg@w3.org>
- Message-ID: <4992B03C.9080402@w3.org>
Ian, you are right in saying that this comment is related to issue #133 and it is my fault not to have checked that. It is also my fault that, at the time, I did not pay enough attention. Apologies for both. As I can see, we have three possible choices related to the exact shape of QL: 1. Have QL include sameAs 2. Have QL include functional properties 3. Have QL include none of the above (letting implementation _add_ one of the two) #1 and #2 are mutually exclusive. The resolution on that issue (leading to #3 which is the current status) was based on a compromise, because we could not decide on either #1 or #2. However, I think there are two issues that may lead us to reconsider this. 1. We have got a comment questioning our choice of profiles (Issue #26, by Eli Lilly[1]). This was echoed by UvA's comment[2]. In a more general sense, we have got several comments that require a better justification for our design choices in terms of user requirements and communities. My feeling is that the compromise solution we reached in resolving Issue #133 is not an adequate one because it leads to unavoidable interoperability issues (let alone the fact that the reasons are not documented or at least I did not find them) 2. The resolution was taken in June 2008. Already at that time the Linking Open Data community and project[3] had a significant push, but this has only intensified since then, with, for example, a separate conference being organized around this subject (let alone the various workshops) or special issue planned for IJSW. Billions of RDF triples are published with millions of, well, owl:sameAs statements used to cross-link various datasets. My feeling is that the two 'small' profiles (QL and RL) may both be attractive for that community if we carefully consider their requirements. That could be a major push in bringing the OWL and RDF worlds closer. Ie, I would still like the WG to (re-)discuss this in view of those LC comments... Cheers Ivan [1] http://lists.w3.org/Archives/Public/public-owl-comments/2009Jan/0033.html [2] http://lists.w3.org/Archives/Public/public-owl-comments/2009Jan/0042.html [3] http://esw.w3.org/topic/SweoIG/TaskForces/CommunityProjects/LinkingOpenData Ian Horrocks wrote: > > As Mike says, we already had an *extensive* discussion about this before > deciding on the current solution. I don't see that the LC comment adds > any new information, so why would be reopen the issue? > > Ian > > > On 4 Feb 2009, at 15:16, Mike Smith wrote: > >> >> On Tue, Feb 3, 2009 at 05:40, Ivan Herman <ivan@w3.org> wrote: >> >>> In the current version of OWL QL, owl:sameAs (if you prefer, same >>> individual assertion:-) is disallowed. Having checked with Boris (and >>> also chatted with Bijan) it seems that the reason is that this leaves it >>> open to possibly extend QL *either* to include owl:sameAs *or* >>> (exclusive 'or') functional properties. >>> >>> In my view, it would be better to include one or the other to the >>> document to make the QL standard profile clearer and cleaner for users. >>> Introducing a loophole of extra extension would reduce the usability of >>> QL in my view, mainly in terms of interoperability. >>> >>> The LOD movement, for better or worse, has already made an extensive use >>> of owl:sameAs in linking billions of triples stemming from public >>> databases. In view of that use case, my proposal is to _add_ the same >>> individual assertion into OWL QL. That would make OWL QL way more >>> attractive for an important user community. >> >> This was one side of the discussion in [ISSUE-133]. I believe that >> the email discussion linked to that issue (including the compromise >> resolution [1]) are relevant when considering this LC comment. >> >> -- >> Mike Smith >> >> Clark & Parsia >> >> [ISSUE-133] http://www.w3.org/2007/OWL/tracker/issues/133 >> [1] http://lists.w3.org/Archives/Public/public-owl-wg/2008Sep/0017.html >> > > -- 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 Wednesday, 11 February 2009 11:02:57 UTC