- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Mon, 25 Jul 2011 09:21:50 +0100
- To: public-prov-wg@w3.org
I'd like to refer to the missing inference I mentioned in a separate thread: I think there is a missing "inference" in the specification. If there isDerivedFrom(e1,e0) holds, then there exists a process execution pe, and roles r0,r1, such that: isGeneratedBy(e1,pe,r1) and use(pe,e0,r0) So, given isDerivedFrom(e1,e0), I would argue that there are potentially four notions of time associated with this derivation: - beginning of pe - end of pe - use of e0 - generation of e1 Paul, in your proposal, were you referring to any of these 4 instants, or did you have another notion of time not captured yet? Luc On 07/24/2011 09:12 PM, Paul Groth wrote: > Something like that...I need to look at the exact definition of derived from. > > Paul > > On Jul 24, 2011, at 20:43, Khalid Belhajjame<Khalid.Belhajjame@cs.man.ac.uk> wrote: > > >> >> Ok, I must admit I didn't understand that. Just to clarify, when one say >> isDerivedFrom(b1,b2,t), does that means that b2 was created at t? >> >> Thanks, khalid >> >> >> On 24/07/2011 18:33, Paul Groth wrote: >> >>> Hi Khalid, >>> >>> I don't think this is what I mean. >>> >>> It's not when the assertion was made. It's when the derivation occurred according to the asserter. >>> >>> Just as with use and generation. It's the time at which these events occur according to the asserter. >>> >>> Thanks >>> Paul >>> >>> On Jul 24, 2011, at 18:08, Khalid Belhajjame<Khalid.Belhajjame@cs.man.ac.uk> wrote: >>> >>> >>>> On 24/07/2011 15:35, Myers, Jim wrote: >>>> >>>>> (The time is not the interval over which the derivation relation is >>>>> valid - in the same way the time on USED is not the time when that >>>>> relation is valid (it would be if the semantics were 'in use during >>>>> interval t') - both just describe the time when an enduring relationship >>>>> was first formed.) >>>>> >>>> Agreed, that what I was hinting to in my last response email to Paul. >>>> The time I was referring to in my email was the validity, but Paul, I >>>> think, was talking about the time where the derivation was formed. >>>> >>>> Which leads me to a new proposal. Instead of having the time as argument >>>> to USE, GENERATION and derivation, e.g., isDerivedFrom(b1,b2,t). Would >>>> it be sensible to assume, instead, that every assertion may be >>>> associated with a time in which it was formed? >>>> >>>> Thanks, Khalid >>>> >>>> >>>>> Jim >>>>> >>>>> >>>>>> -----Original Message----- >>>>>> From: public-prov-wg-request@w3.org [mailto:public-prov-wg- >>>>>> request@w3.org] On Behalf Of Khalid Belhajjame >>>>>> Sent: Sunday, July 24, 2011 8:27 AM >>>>>> To: Paul Groth >>>>>> Cc: Provenance Working Group WG; Provenance Working Group Issue >>>>>> >>>>> Tracker >>>>> >>>>>> Subject: Re: PROV-ISSUE-43 (derivation-time): Deriviation should have >>>>>> associated time [Conceptual Model] >>>>>> >>>>>> >>>>>> Hi Paul, >>>>>> >>>>>> On 24/07/2011 13:13, Paul Groth wrote: >>>>>> >>>>>>> Hi Khalid >>>>>>> But why can't I say that a newspaper article is derived from a >>>>>>> >>>>> picture at a >>>>> >>>>>> particular time? Or for that matter over a period of time. >>>>>> >>>>>> The way I see it, is that there will be a bob representing the >>>>>> >>>>> newspaper article >>>>> >>>>>> and another representing the picture. If there is evidence that the >>>>>> >>>>> latter is >>>>> >>>>>> derived from the former, then the derivation will always hold between >>>>>> >>>>> those >>>>> >>>>>> two bobs. >>>>>> >>>>>> Now, that I am writing this email, I am wondering whether we are >>>>>> >>>>> referring to >>>>> >>>>>> the same notion of time. In your statement, isDerivedFrom(b1,b2,t), I >>>>>> >>>>> think you >>>>> >>>>>> mean t is used to refers to the time in which the derivation assertion >>>>>> >>>>> was >>>>> >>>>>> made, whereas what I was thinking of is the (period of) time in which >>>>>> >>>>> the >>>>> >>>>>> derivation holds. Is that the case? >>>>>> >>>>>> Thanks, khalid >>>>>> >>>>>>> The time is when the derivation occurred not when it applies. >>>>>>> >>>>>>> Thanks >>>>>>> Paul >>>>>>> >>>>>>> On Jul 24, 2011, at 13:06, Khalid >>>>>>> >>>>>> Belhajjame<Khalid.Belhajjame@cs.man.ac.uk> wrote: >>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I think that "Use" and "Generation" should be associated with time. >>>>>>>> However, I don't think we should associate time to derivation. >>>>>>>> I would argue that isDerivedFrom(b1,b2) holds all time. Although b1 >>>>>>>> and >>>>>>>> b2 may no longer exist, isDerivedFrom(b1,b2) is still valid. >>>>>>>> >>>>>>>> Thanks, khalid >>>>>>>> >>>>>>>> >>>>>>>> On 23/07/2011 16:46, Provenance Working Group Issue Tracker wrote: >>>>>>>> >>>>>>>>> PROV-ISSUE-43 (derivation-time): Deriviation should have >>>>>>>>> >>>>> associated >>>>> >>>>>>>>> time [Conceptual Model] >>>>>>>>> >>>>>>>>> http://www.w3.org/2011/prov/track/issues/43 >>>>>>>>> >>>>>>>>> Raised by: Paul Groth >>>>>>>>> On product: Conceptual Model >>>>>>>>> >>>>>>>>> Other relationships have time associated with them (e.g. use, >>>>>>>>> generation, control) >>>>>>>>> >>>>>>>>> There is no optional time associated with derivation. >>>>>>>>> >>>>>>>>> Suggested resolution is to add the following to the definition of >>>>>>>>> >>>>>> isDerivedFrom: >>>>>> >>>>>>>>> - May contain a "derived from time" t, the time or time intervals >>>>>>>>> when b1 was derived from b2 >>>>>>>>> >>>>>>>>> Example: >>>>>>>>> isDerivedFrom(b1,b2, t) >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>> >> > -- 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 Monday, 25 July 2011 08:22:20 UTC