- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Mon, 07 Nov 2011 11:46:45 +0000
- To: public-prov-wg@w3.org
Hi Satya, The WG decided to drop this constraint on attributes. I conclude we can close this issue. Let me know if it's not the case. Thanks, Luc On 10/10/2011 12:36 AM, Provenance Working Group Issue Tracker wrote: > PROV-ISSUE-122: Constraint on wasGeneratedBy (PROV-DM and PROV-OM) [Conceptual Model] > > http://www.w3.org/2011/prov/track/issues/122 > > Raised by: Satya Sahoo > On product: Conceptual Model > > The following constraint is defined on wasGeneratedBy in the PROV-DM document (as on Oct 9, 2011): > "Given a process execution pe, entity e, role r, and optional time t, if the assertion wasGeneratedBy(e,pe,r) or wasGeneratedBy(e,pe,r,t) holds, the values of some of e's attributes are determined by the activity denoted by pe and the entities used by pe. Only some (possibly none) of the attributes values may be determined since, in an open world, not all used entities may have been asserted." > > Issue: This constraint seems to be self-contradictory due to the two phrases "...the values of some of e's attributes are determined by the activity denoted by pe..." and "Only some (possibly none) of the attributes values may be determined...". > > In addition, this constraint cannot be enforced, since which attributes will be determined are not specified and given the use of open world assumption, there be always some attribute that is not currently associated with the entity. > > Overall, this constraint does not help either in inferring new knowledge from existing information or allow "validation/checking" of existing knowledge - which are the standard uses of rules/constraints. Hence, the suggestion is to remove this constraint. > > > > -- 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, 7 November 2011 11:47:13 UTC