- From: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
- Date: Sun, 24 Jul 2011 17:08:16 +0100
- To: "Myers, Jim" <MYERSJ4@rpi.edu>
- CC: Paul Groth <p.t.groth@vu.nl>, Provenance Working Group WG <public-prov-wg@w3.org>, Provenance Working Group Issue Tracker <sysbot+tracker@w3.org>
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) >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> > >
Received on Sunday, 24 July 2011 16:08:47 UTC