W3C home > Mailing lists > Public > public-prov-wg@w3.org > September 2011

Re: PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually "IVP of" each other [Conceptual Model]

From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Date: Thu, 29 Sep 2011 15:55:41 +0100
Message-ID: <EMEW3|49d698b1d90f2b5e2735e4c77ce52f0en8SFyk08L.Moreau|ecs.soton.ac.uk|4E8486ED.2000606@ecs.soton.ac.uk>
To: public-prov-wg@w3.org
Or can it be on entities? We could offer the option to express the 
characterization interval in the entity expression.

Luc

On 09/29/2011 03:52 PM, Myers, Jim wrote:
>
> So the missing functionality is time constraints on the duration of 
> the complementOf relation? Or is something else/additional needed?
>
> Jim
>
> *From:* public-prov-wg-request@w3.org 
> [mailto:public-prov-wg-request@w3.org] *On Behalf Of *Cresswell, Stephen
> *Sent:* Thursday, September 29, 2011 10:16 AM
> *To:* public-prov-wg@w3.org
> *Subject:* RE: PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually 
> "IVP of" each other [Conceptual Model]
>
> Hi Jim,
>
> Thanks for your comments.  Sorry for the delay in responding -- please 
> see responses inline below.
>
> Stephen Cresswell
>
> ------------------------------------------------------------------------
>
> *From:* Myers, Jim [mailto:MYERSJ4@rpi.edu]
> *Sent:* 26 September 2011 16:35
> *To:* Cresswell, Stephen; Paolo Missier; public-prov-wg@w3.org
> *Subject:* RE: PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually 
> "IVP of" each other [Conceptual Model]
>
> Jim Myers wrote:
> > I'm not sure what of 29 and 57 then survive as unresolved concerns - 
> perhaps whether transitivity can be defined?
>
> I have two concerns (or perhaps the same concern approached from two 
> directions).
>
> (1)
> I think that the assertion wasComplementOf(B,A) implicitly defines a 
> new entity.
> The new entity has a time interval which is the temporal intersection 
> of those of A and B.
> The new entity has a set of attribute-value pairs which is the union 
> of those of A and B.
>
> However, if I want to make this new entity explicit, I can't.  The 
> vocabulary I need to use to state its relationship to A and B is missing.
>
> ---- Why not C with attributes location and membership that is a 
> complement of A and B?
>
> If we have the assertions: wasComplementOf(B,A), wasComplement(C,A), 
> wasComplement(C,B), we still haven't expressed that the time interval 
> of C is within those of both A and B.  Because we couldn't express 
> that, we couldn't infer C's attributes, although of course we can 
> assert them.
>
>
> (2)
> One use for the original IVPof was (I thought) to relate together 
> long-term entities (e.g. Luc-over-his-lifetime) with shorter-term 
> entities describing states (e.g. Luc-in-Boston).  Now it seems that 
> the strongest assertion that I can make about the relationship of 
> these two entities is:
>
>   wasComplementOf( Luc-in-Boston, Luc-over-his-lifetime )
>
> ... but this just asserts that Luc's visit to Boston *overlapped* with 
> his lifetime, which is weaker than what I wanted to assert.
>
> --what's missing? I take this as meaning there was a Luc-in-Boston 
> entity that is an alternate characterization of Luc that is only valid 
> during his trip to Boston, not that these entities just coexist in 
> time. Do you want something more than that or do you think that 
> interpretation is not captured in the definition of complementOf?
>
> I want to express that Luc-in-Boston was entirely within 
> Luc-over-his-lifetime, and therefore everything invariant in 
> Luc-over-his-lifetime is also invariant for the whole duration of 
> Luc-in-Boston.  Also, I want to make the transitive inference of the 
> same relationship between Luc-at-MIT and Luc-over-his-lifetime.
>
>
> If I also want to describe a visit to MIT that Luc made while in 
> Boston, I could also assert
>
>   wasComplementOf( Luc-at-MIT, Luc-in-Boston )
>
> Since the assertions are quite vague, we can't infer that 
> Luc-over-his-lifetime contained Luc-at-MIT, and we can't even infer 
> that they overlapped.
> I think it would be useful to be able to make some stronger assertions 
> that allow transitivity to be used here.  At some point during its 
> evolution, IVPof was close to being that helpful transitive relation, 
> but now its gone.  I think we still need it.
>
> --- What's missing from the complementOf definition (that was in 
> ivpOf?)? Doesn't your assumption above that there's a new entity that 
> is the intersection of two complementary entities force transitivity 
> during the intersection interval?
>
> I don't see how to express that using wasComplementOf.
>
>
> Stephen Cresswell
>
> -----Original Message-----
> From: Myers, Jim [mailto:MYERSJ4@rpi.edu]
> Sent: Fri 23/09/2011 18:21
> To: Cresswell, Stephen; Paolo Missier; public-prov-wg@w3.org
> Subject: RE: PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually 
> "IVP  of"  each other  [Conceptual Model]
>
> When I read the current document, I see complementOF is defined as 
> one-way - you can assert it in both directions, but the text talks 
> about a case where B is a complementOf A but not the reverse. Can the 
> editors confirm that's the intent? If so, perhaps we can move to 
> refining text to avoid the perception that symmetry is required (i.e. 
> talk about the asymmetric case first...). I'm not sure what of 29 and 
> 57 then survive as unresolved concerns - perhaps whether transitivity 
> can be defined?
>
> Cheers,
>  Jim
>
> > -----Original Message-----
> > From: public-prov-wg-request@w3.org 
> <mailto:public-prov-wg-request@w3.org> [mailto:public-prov-wg-
> > request@w3.org <mailto:request@w3.org>] On Behalf Of Cresswell, Stephen
> > Sent: Friday, September 23, 2011 10:15 AM
> > To: Paolo Missier; public-prov-wg@w3.org <mailto:public-prov-wg@w3.org>
> > Subject: RE: PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually "IVP
> > of" each other [Conceptual Model]
> >
> >
> > Hi Paolo,
> >
> > Yes, I agree that the current wasComplementOf can be symmetrical, and I
> > have no objection to closing issue 29.
> >
> > I do still think that a concept of IVPof that is antisymmetric and 
> transitive, so
> > that "B IVPof A" means something like "B and A describe the same stuff,
> > and B's interval is within A's interval" is a simpler and stronger 
> concept.  It
> > can co-exist with wasComplementOf, and it can be used to define (a
> > symmetric form of) wasComplementOf (which admittedly doesn't match
> > the current definition).
> > i.e.
> >   (B wasComplementOf A) <=> exists C.(C IVPof A & C IVPof B)
> >
> > Since wasComplementOf is a relation that only holds over the temporal
> > intersection A and B anyway, then saying it with this IVPof at least 
> makes
> > you introduce an entity C that models the relevant interval.
> >
> > However, I think that's basically what Graham said and it is a 
> different issue
> > - PROV-ISSUE-57.
> >
> > Stephen Cresswell
> >
> > Tel:  +44 (0) 01603 69 6926
> >
> > Web: www.tso.co.uk <http://www.tso.co.uk>
> >
> >
> >
> >
> > -----Original Message-----
> > From: public-prov-wg-request@w3.org 
> <mailto:public-prov-wg-request@w3.org>
> > [mailto:public-prov-wg-request@w3.org] On Behalf Of Paolo Missier
> > Sent: 23 September 2011 12:06
> > To: public-prov-wg@w3.org <mailto:public-prov-wg@w3.org>
> > Subject: Re: PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually "IVP
> > of" each other [Conceptual Model]
> >
> > Hi,
> >
> > as we are going through older issues, this one seems to have been
> > superseded by the current version of the model. We propose to close it
> > pending review (that means, Stephen can you please call in with your
> > current view on this, thank you).
> >
> > Specifically:  IVP-of has been replaced by ComplementOf, which *does*
> > allow for symmetry.
> >
> > -Paolo
> >
> >
> > On 7/11/11 12:22 PM, Provenance Working Group Issue Tracker wrote:
> > > PROV-ISSUE-29 (mutual-iVP-of): can two bobs be mutually "IVP of" each
> > other  [Conceptual Model]
> > >
> > > http://www.w3.org/2011/prov/track/issues/29
> > >
> > > Raised by: Stephen Cresswell
> > > On product: Conceptual Model
> > >
> > >
> > > As it currently stands, I believe that it does not exclude the
> > possibility that two bobs may be mutually "IVP of" each other -
> > > i.e. you could have bobs A, B such that (B IVPof A)&  (A IVPof B), and
> > this is surely not intended.
> > >
> > > This could arise if, for bobs A, B :
> > > - A and B both represent the same entity
> > > - A and B share some immutable properties, and they have corresponding
> > values.
> > > - B has some immutable properties which correspond to mutable
> > properties of A
> > > - A has some immutable properties which correspond to mutable
> > properties of B
> > >
> > > Possibly the asserter-defined test (included in "IPV of" definition)
> > that real world states modelled by A and B are "consistent" may disallow
> > > "IPV of" in this situation.  However, unless that is guaranteed, I
> > think that the definition of "B IPV of A" (if it is still to have a
> > definition) should additionally require that:
> > > "A has no immutable properties which correspond to mutable properties
> > of B"
> > >
> > > Stephen
> > >
> > >
> > >
> > >
> >
> >
> > --
> > -----------  ~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
> >
> >
> >
> > ______________________________________________________________
> > __________
> > This e-mail has been scanned for all viruses by Star. The
> > service is powered by MessageLabs. For more information on a proactive
> > anti-virus service working around the clock, around the globe, visit:
> > http://www.star.net.uk
> > ______________________________________________________________
> > __________
> >
> > **************************************************************
> > *********************************
> > This email, including any attachment, is confidential and may be legally
> > privileged.  If you are not the intended recipient or if you have 
> received this
> > email in error, please inform the sender immediately by reply and 
> delete all
> > copies from your system. Do not retain, copy, disclose, distribute or
> > otherwise use any of its contents.
> >
> > Whilst we have taken reasonable precautions to ensure that this email has
> > been swept for computer viruses, we cannot guarantee that this email does
> > not contain such material and we therefore advise you to carry out 
> your own
> > virus checks. We do not accept liability for any damage or losses 
> sustained
> > as a result of such material.
> >
> > Please note that incoming and outgoing email communications passing
> > through our IT systems may be monitored and/or intercepted by us 
> solely to
> > determine whether the content is business related and compliant with
> > company standards.
> > **************************************************************
> > *********************************
> >
> > The Stationery Office Limited is registered in England No. 3049649 at 10
> > Eastbourne Terrace, London, W2 6LG
> >
> >
>
>
> ________________________________________________________________________
> This e-mail has been scanned for all viruses by Star. The
> service is powered by MessageLabs. For more information on a proactive
> anti-virus service working around the clock, around the globe, visit:
> http://www.star.net.uk
> ________________________________________________________________________
>
>
> ________________________________________________________________________
> This e-mail has been scanned for all viruses by Star. The
> service is powered by MessageLabs. For more information on a proactive
> anti-virus service working around the clock, around the globe, visit:
> http://www.star.net.uk
> ________________________________________________________________________
>

-- 
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 Kingdom                     http://www.ecs.soton.ac.uk/~lavm
Received on Thursday, 29 September 2011 14:56:29 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 13:06:42 GMT