- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Wed, 15 Feb 2012 12:12:26 +0000
- To: Satya Sahoo <satya.sahoo@case.edu>
- CC: public-prov-wg@w3.org
- Message-ID: <EMEW3|1cb53b9f363a4560ea80a8bfa167229co1ECCY08L.Moreau|ecs.soton.ac.uk|4F3BA12A>
Hi Satya, This is issue is now closed. Luc On 02/14/2012 10:54 PM, Satya Sahoo wrote: > Hi Luc, > I am fine with closing this particular issue (I will be raising issues > against the TPWD separately). > > Thanks. > > Best, > Satya > > On Thu, Dec 8, 2011 at 6:04 AM, Luc Moreau <L.Moreau@ecs.soton.ac.uk > <mailto:L.Moreau@ecs.soton.ac.uk>> wrote: > > Hi Satya, > > This is again *very frustrating*. This PROV-ISSUE-50, and your last > communication on this dates back from October 2nd!!!! > > http://lists.w3.org/Archives/Public/public-prov-wg/2011Oct/0007.html > > You have not responded to my message on Oct 3rd > http://lists.w3.org/Archives/Public/public-prov-wg/2011Oct/0009.html > and November 30th > http://lists.w3.org/Archives/Public/public-prov-wg/2011Nov/0419.html > > Further comments below. > > On 12/07/2011 02:22 AM, Provenance Working Group Issue Tracker wrote: > > PROV-ISSUE-200: Section 6.3 (PROV-DM as on Dec 5) [prov-dm] > > http://www.w3.org/2011/prov/track/issues/200 > > Raised by: Satya Sahoo > On product: prov-dm > > Hi, > The following are my comments for Section 6.3 of the PROV-DM > (as on Dec 5): > > Section 6.3 > 1. Given: > > "An information flow ordering record is a representation that > an entity was generated by an activity, before it was used by > another activity." > > How does the constraint: > > "Given two activity records denoted by a1 and a2, if the > record wasInformedBy(a2,a1) holds, then the following temporal > constraint holds: the start event of the activity record > denoted by a1 precedes the end event of the activity record > denoted by a2." > > make sense? > > Detailed comment: Let us consider the scenario: "a chemical > reagent r1 was generated by activity a1 in September 2011" and > "r1 was used by researcher in experiment activity a2 in > December 2011". From a provenance perspective, we simply state > r1 was generated before it was used - where is the relevance > of activity ordering in above scenario (entity was generated > before it was used)? > > you will note that the above constraint is a necessary condition > and not a sufficient condition! > > The point about information flow ordering is that the entity does > not have to be explicitly mentioned. It's an existential > quantifier over an entity. > > If you activity a1 had started after the end of a2, it would have > been impossible to have this entity r1 generated by a1 and used by a2. > > Further, activity ordering is important in provenance from a > very different perspective - "analyzing provenance of bank > transactions to justify penalty fee for customer c1 - the > $100.00 deposit activity da1 took place before or after $80.00 > withdrawal activity wa1 happened in account with starting > balance of $5.00". So, if da1 happened before wa1 there should > not be any penalty fee, otherwise customer has to pay fee for > withdrawing more money than was available in the account. > > > This example is handled by having various account entities for the > various balances. > I don't think we need an explicit activity ordering here. > > Clearly, the informedBy property does not address the > requirement of activity ordering for provenance. In addition, > the current definition of informedBy for representing whether > entity was generated before it was used does not need activity > information - it can be asserted either in terms of event > ordering or temporal ordering. I believe we should remove > wasInformedBy or move it out of activity ordering section. > > > What do you mean by *clearly*? > How can we assert this by event/temporal ordering ? > 1. The relations precedes/follows do not belong to the data model > (they are used in interpretation) > 2. The interpretation over wasInformedBy is a necessary condition, > not a sufficient condition. > There needs to be an entity used and generated between > these activities, though we dont have to assert it. > > > 2. "The relationship wasInformedBy is not transitive. Indeed, > consider the records wasInformedBy(a2,a1) and > wasInformedBy(a3,a2), the record wasInformedBy(a3,a1), may not > necessarily hold, as illustrated by the following event line." > > Comment: It is not clear from the description and the figure, > why wasInformedBy is not transitive? It is difficult to > interpret the figure without additional description. > > > Tim mentioned this. THis will be dealt with. > > 3. "Given two activity records identified by a1 and a2, the > record wasStartedBy(a2,a1) holds if and only if there exist an > entity record identified by e and some attributes gAttr and > sAttr, such that wasGeneratedBy(e,a1,gAttr) and > wasStartedBy(a2,e,sAttr) hold." > > Comment: The above definition and related example for > wasStartedBy are not clear at all. What is meant by the > statement that "spawn-request" was generated by a1 and > "spawn-request" is in a wasStartedBy relation with a2, hence > a1 and a2 also have a wasStartedBy relation? Is > "spawn-request" supposed to represent control message > exchanged between a1 and a2 or something else? > > > There were problems in the text. I hopefully fixed them. Can you > check? > > Luc > > Thanks. > > Best, > Satya > > > > > > -- > 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> > > > -- 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 Wednesday, 15 February 2012 12:12:58 UTC