- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Tue, 27 Mar 2012 22:37:22 +0100
- To: James Cheney <jcheney@inf.ed.ac.uk>
- CC: Jim McCusker <mccusj@rpi.edu>, public-prov-wg@w3.org
- Message-ID: <EMEW3|d8ade5570b04aeff3ef8095967b7f957o2QMci08L.Moreau|ecs.soton.ac.uk|4F723312>
Hi James, You write "due to the requirement that entity intervals overlap". You will notice that the current definition in English appearing in http://dvcs.w3.org/hg/prov/raw-file/default/model/working-copy/wd5-prov-dm-alternate.html does not seem to require an entity interval overlap. Can the semantics support this too? Regards, Luc On 27/03/12 20:42, James Cheney wrote: > Hi, > > The formal semantics draft for WD3 [1] addressed this, and the bottom > line is currently: > > alternateOf: reflexive, symmetric, NOT transitive (due to the > requirement that entity intervals overlap). > > specializationOf: reflexive, transitive, NOT symmetric, NOT > antisymmetric (no requirement that two mutually specializing entities > are equal, but we could add this). > > We can easily adjust the formalization of specializationOf to not be > reflexive (or to require that it is irreflexive). > > I plan to read the current version of WD5 over the next day or so and > update this. I don't think the informal definitions have changed that > much though. > > Part of the point of the formal semantics is to provide a > rationalization for these types of properties, especially where there > has been a lot of discussion or disagreement. So I would appreciate > feedback on the formal semantics from people who are interested in > these questions. I will also notify the list by Friday when the > revised version is ready. (At a conference this week so it's been > hard to find time for this since my talk was today.) > > --James > > [1] http://www.w3.org/2011/prov/wiki/FormalSemanticsWD3 > > On Mar 27, 2012, at 7:28 PM, Luc Moreau wrote: > >> Hi Jim, >> >> Agreed, we could be silent about reflexivity, which means we don't >> say whether specializationOf is >> reflexive or irreflexive. >> >> That's a conservative position, I am fine with. >> >> >> The English definition uses the term 'more constrained' which is >> probably too vague to decide one or the other. >> >> An entity is a specialization of another if they both refer to some >> common thing >> but the former is a *more constrained* entity than the former. The >> common entity does not need to be identified. >> >> >> Luc >> >> >> On 03/27/2012 05:20 PM, Jim McCusker wrote: >>> I'm not sure if it is or not. I'm willing to support proposals as to >>> why it might be, but I haven't seen any good arguments for it yet. >>> Even if we think it might be, we may want to hold off on declaring it. >>> >>> Neither rdfs:subClassOf or skos:broader are reflexive, and I think >>> the same arguments apply to making them reflexive. People who are >>> interested in having a reflexive specializationOf could make a >>> subproperty (if it's domain specific) or superproperty (if they >>> think that it always holds), depending on their needs. However, if >>> we define it to be reflexive ourselves, we complicate matters for >>> those who think that it isn't. >>> >>> Jim >>> >>> On Tue, Mar 27, 2012 at 12:09 PM, Luc Moreau >>> <L.Moreau@ecs.soton.ac.uk <mailto:L.Moreau@ecs.soton.ac.uk>> wrote: >>> >>> Hi, >>> As we discuss axioms of specialization/alternateOf >>> >>> is specializationOf reflexive? >>> >>> Luc >>> >>> >>> On 03/27/2012 03:52 PM, Stian Soiland-Reyes wrote: >>> >>> alt1 and alt2 is good. It is fairly obvious (but should be >>> explained >>> in constraints) that alternateOf(a, b) indirectly implies >>> alternateOf(b, a), as it implies >>> >>> specializationOf(a, X) >>> specializationOf(b, X) >>> >>> and that implies: >>> >>> alternateOf(b, a) >>> alternateOf(a, b) >>> >>> >>> Would we need to say that if >>> >>> alternateOf(a, b) >>> alternateOf(a, c) >>> >>> it does not imply: >>> >>> alternateOf(b, c) >>> >>> ? >>> >>> >>> On Mon, Mar 26, 2012 at 22:46, Jim McCusker<mccusj@rpi.edu >>> <mailto:mccusj@rpi.edu>> wrote: >>> >>> Do they need fully contextualized names? Can they just >>> be a and b, or x and >>> y? I'm pretty sure this isn't a qualified relation... >>> >>> Jim >>> >>> >>> On Mon, Mar 26, 2012 at 5:41 PM, Luc >>> Moreau<L.Moreau@ecs.soton.ac.uk >>> <mailto:L.Moreau@ecs.soton.ac.uk>> >>> wrote: >>> >>> >>> BTW, has somebody got better names for first and >>> second alternate? >>> >>> >>> http://dvcs.w3.org/hg/prov/raw-file/default/model/working-copy/wd5-prov-dm-alternate.html#alternate.firstAlternate >>> >>> http://dvcs.w3.org/hg/prov/raw-file/default/model/working-copy/wd5-prov-dm-alternate.html#alternate.secondAlternate >>> >>> Thanks, >>> Luc >>> >>> >>> On 26/03/12 22:38, Luc Moreau wrote: >>> >>> Hi Paolo, >>> >>> I have updated the text to make it clear that the >>> common entity does not >>> need >>> to be identified. >>> >>> http://dvcs.w3.org/hg/prov/rev/21b96bf05727 >>> >>> Cheers, >>> Luc >>> >>> On 26/03/12 15:59, Paolo Missier wrote: >>> >>> Luc >>> >>> >>> On 3/26/12 2:54 PM, Luc Moreau wrote: >>> >>> Dear all, >>> >>> Thanks for your very useful suggestions. >>> >>> I have drafted a revised section in a separate file >>> >>> http://dvcs.w3.org/hg/prov/raw-file/default/model/working-copy/wd5-prov-dm-alternate.html >>> >>> Does capture what has been discussed so far? >>> >>> I think so. To me it is important that when we say >>> " They are both specialization of an (unspecified) >>> entity." eg in the >>> first example, it is clear that there no obligation >>> to say anything about >>> the common entity that they specialize. This, >>> however, contrasts with the >>> definition itself: >>> " An entity is alternate of another if they are both >>> a specialization of >>> some common entity." >>> It is not clear what to make of this defining >>> property of alternates -- it >>> gives an existential condition which is not >>> actionable in general. So to me >>> this is potentially confusing. >>> >>> >>> Also, if specialization(a,b) is it the case that >>> alternateOf(a,b)? >>> >>> no. I recall that we've been there before. At some >>> point there was a >>> discussion on specialization having a "top" and >>> being transitive and >>> therefore, with this additional inferences, >>> everything would collapse. >>> >>> Regards, >>> -Paolo >>> >>> >>> Regards, >>> Luc >>> >>> On 25/03/2012 17:16, Timothy Lebo wrote: >>> >>> >>> On Mar 25, 2012, at 9:43 AM, Jim McCusker wrote: >>> >>> On Sun, Mar 25, 2012 at 3:18 AM, Graham >>> Klyne<GK@ninebynine.org <mailto:GK@ninebynine.org>> >>> wrote: >>> >>> In my review comments which I think you have yet >>> to get round to, I >>> question whether we actually need to have these >>> concepts in the DM. >>> >>> Originally, by my recollection, they were >>> introduced to explain the >>> relationship between provenance entities and >>> (possibly dynamic) real world >>> things. With the looser description of the >>> provenance model terms, I don't >>> see why this level of detail is needed in the >>> data model. >>> >>> >>> Then you don't recollect correctly. >>> >>> >>> I remember IPV-of as the "relationship between >>> provenance entities and >>> (possibly dynamic) real world things", but >>> specializationOf has developed >>> into a more general association between entities >>> that can include this >>> original purpose. Indeed, eg-19 [1] is using alt and >>> specOf for _exactly_ >>> this original "frozen snapshot of changing things" >>> notion -- applied to >>> datasets and web services. >>> >>> Instead of digging up the archives, perhaps we can >>> rally around altOf and >>> specOf being the tools we use to associate (and make >>> sense of) assertions >>> made by the combinations of scruffy and proper >>> provenance. >>> (Like Simon's extension to Stian's BBC example). In >>> addition, it's an >>> incredibly useful construct for one's own "proper" >>> modeling. >>> >>> [1] >>> http://www.w3.org/2011/prov/wiki/Eg-19-derived-named-graph-attribution >>> >>> They were defined because there was an >>> acknowledgement that there were >>> multiple symbols that denoted a common thing in the >>> world. Sometimes they >>> reflected different aspects of the same thing >>> (alternativeOf) and sometimes >>> they had a subsumptive quality (specializationOf). >>> >>> >>> I think these previous two statements contradict >>> (and steer scarily >>> towards owl:sameAs, which alt and specOf are >>> certainly _not_) >>> Different aspects of the same thing are not the same >>> things. >>> >>> -Tim >>> >>> >>> Jim >>> -- >>> Jim McCusker >>> Programmer Analyst >>> Krauthammer Lab, Pathology Informatics >>> Yale School of Medicine >>> james.mccusker@yale.edu >>> <mailto:james.mccusker@yale.edu> | (203) 785-6330 >>> <tel:%28203%29%20785-6330> >>> http://krauthammerlab.med.yale.edu >>> <http://krauthammerlab.med.yale.edu/> >>> >>> PhD Student >>> Tetherless World Constellation >>> Rensselaer Polytechnic Institute >>> mccusj@cs.rpi.edu <mailto:mccusj@cs.rpi.edu> >>> http://tw.rpi.edu <http://tw.rpi.edu/> >>> >>> >>> >>> >>> -- >>> ----------- ~oo~ -------------- >>> Paolo Missier - Paolo.Missier@newcastle.ac.uk >>> <mailto:Paolo.Missier@newcastle.ac.uk>, >>> pmissier@acm.org <mailto:pmissier@acm.org> >>> School of Computing Science, Newcastle University, UK >>> http://www.cs.ncl.ac.uk/people/Paolo.Missier >>> >>> >>> >>> >>> >>> -- >>> Jim McCusker >>> Programmer Analyst >>> Krauthammer Lab, Pathology Informatics >>> Yale School of Medicine >>> james.mccusker@yale.edu <mailto:james.mccusker@yale.edu> >>> | (203) 785-6330 <tel:%28203%29%20785-6330> >>> http://krauthammerlab.med.yale.edu >>> <http://krauthammerlab.med.yale.edu/> >>> >>> PhD Student >>> Tetherless World Constellation >>> Rensselaer Polytechnic Institute >>> mccusj@cs.rpi.edu <mailto:mccusj@cs.rpi.edu> >>> http://tw.rpi.edu <http://tw.rpi.edu/> >>> >>> >>> >>> >>> >>> -- >>> Professor Luc Moreau >>> Electronics and Computer Science tel: +44 23 8059 4487 >>> <tel:%2B44%2023%208059%204487> >>> University of Southampton fax: +44 23 8059 2865 >>> <tel:%2B44%2023%208059%202865> >>> Southampton SO17 1BJ email: >>> l.moreau@ecs.soton.ac.uk <mailto:l.moreau@ecs.soton.ac.uk> >>> United Kingdom http://www.ecs.soton.ac.uk/~lavm >>> <http://www.ecs.soton.ac.uk/%7Elavm> >>> >>> >>> >>> >>> >>> -- >>> Jim McCusker >>> Programmer Analyst >>> Krauthammer Lab, Pathology Informatics >>> Yale School of Medicine >>> james.mccusker@yale.edu <mailto:james.mccusker@yale.edu> | (203) >>> 785-6330 >>> http://krauthammerlab.med.yale.edu <http://krauthammerlab.med.yale.edu/> >>> >>> PhD Student >>> Tetherless World Constellation >>> Rensselaer Polytechnic Institute >>> mccusj@cs.rpi.edu <mailto:mccusj@cs.rpi.edu> >>> http://tw.rpi.edu <http://tw.rpi.edu/> >> >> -- >> Professor Luc Moreau >> Electronics and Computer Science tel: +44 23 8059 4487 >> University of Southampton fax: +44 23 8059 2865 >> Southampton SO17 1BJ email:l.moreau@ecs.soton.ac.uk >> United Kingdomhttp://www.ecs.soton.ac.uk/~lavm >> > > > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. >
Received on Tuesday, 27 March 2012 21:39:25 UTC