- From: Stephan Zednik <zednis@rpi.edu>
- Date: Wed, 21 Dec 2011 11:12:46 -0700
- To: Simon Miles <simon.miles@kcl.ac.uk>
- Cc: Provenance Working Group WG <public-prov-wg@w3.org>
Hi Simon, Luc, I believe that Tim and I are in agreement on this issue. I raised the issue because there was some discussion about Activities having roles in a PROV-O telecon (this was several weeks ago) and that conflicted with the existing definition of role. I was also curious if there would be any objection to the assertion that a generated entity has a function in the activity that generates it. Time's responses, and the lack of any further responses has led me to believe that: 1) The general understanding of the usage of roles in a qualified wasGeneratedBy fits the existing definition for roles, and I have not seen any further discussion of activities having roles. 2) There is general agreement (based on the lack of objections) that a generated entity can play a part/function in the activity that generates it. I believe this issue can be closed. --Stephan On Dec 21, 2011, at 4:13 AM, Simon Miles wrote: > Hi Stephan, Tim, > It seems this discussion has different aspects relating to PROV-O, > PROV-DM and the primer. > > Could one of you raise the proposed changes to the primer with > rationale as a separate issue specifically for that document? The > "outputAggregatedDataset" naming suggestion makes sense to me and > seems a good idea, but I'm not clear on the rationale behind the > typing suggestion, so would be good if you can spell it out. > > Thanks, > Simon > On 21 December 2011 10:42, Luc Moreau <L.Moreau@ecs.soton.ac.uk> wrote: >> Hi Stephan and Tim, >> >> Have we converged on this issue? Is there something that needs to be >> addressed in the >> prov-dm document? >> >> If yes, can you clarify? If not, then I propose we close the issue. >> >> Regards, >> Luc >> >> >> On 11/22/2011 04:25 PM, Timothy Lebo wrote: >> >> >> On Nov 14, 2011, at 5:23 PM, Provenance Working Group Issue Tracker wrote: >> >> >> PROV-ISSUE-150: question on formal semantics of role in wasGeneratedBy >> relation [Formal Semantics] >> >> http://www.w3.org/2011/prov/track/issues/150 >> >> Raised by: Stephan Zednik >> On product: Formal Semantics >> >> I am slightly confused about the formal semantics of the role qualifier in a >> wasGeneratedBy relation. >> >> from http://www.w3.org/TR/prov-dm/#prov-dm-overview >> >> "Qualifiers can be associated to relations, namely use and wasGeneratedBy, >> in order to further characterize their nature. Role is a pre-defined >> qualifier." >> >> and from http://www.w3.org/TR/prov-dm/#expression-qualifier >> >> "The PROV data model introduces the qualifier role in the PROV-DM namespace >> to denote the function of a characterized thing with respect to an activity, >> in the context of a use/generation/control relation. The value associated >> with a role attribute must be conformant with Literal." >> >> I have sensed confusion in the prov-o discussions as to whether the role in >> a generation is played by the process execution or the generated entity. >> >> >> >> I don't think many people have misinterpreted the prov:hadRole's value to be >> the role of an Activity; it is the role of the Entity, as you cite from the >> DM above. >> >> >> Can a generated entity play a role in the activity that generates it? >> >> >> Absolutely >> >> Can a process execution play a role, that is be the characterized thing >> that has a function in an activity? >> >> >> >> The Activity is self-roling. It's existence establishes its characterization >> and can be modeled explicitly by specializing Activity. >> >> >> Does the definition of role need to be changed? >> >> >> I don't think so. >> >> >> I know discussion of role has taken up a lot of time, this sure has turned >> out to be a tricky issue, but I think getting qualifiers right is worth it. >> >> There is an example in the primer, >> http://dvcs.w3.org/hg/prov/raw-file/default/primer/Primer.html#roles-1, >> >> >> >> 1) The name ex1:aggregated seems a bit odd, since it sounds like it is the >> output and not the activity itself. >> >> 2) I'd suggest adding types for Activities in the examples. >> >> but I am not sure if it is representative of the intent for role on a >> generation relation. >> >> ex1:aggregated >> prov:hadQualifiedGeneration [ a prov:Generation ; >> prov:hadQualifiedEntity ex1:aggregate1 ; >> prov:hadRole ex1:aggregatedData >> ] . >> >> >> >> Perhaps the example >> from http://www.w3.org/2011/prov/wiki/Qualifed_Involvements_in_PROV-O#Qualified_Generation_with_Roles >> would make roles of generated entities more clear: >> >> :pe >> a prov:ProcessExecution; >> >> prov:generated :output; >> prov:hadQualifiedGeneration [ >> a prov:Generation; >> prov:hadQualifiedEntity :output; >> prov:hadRole workflow:output; >> ]; >> >> prov:generated :metadata; >> prov:hadQualifiedGeneration [ >> a prov:Generation; >> prov:hadQualifiedEntity :metadata; >> prov:hadRole workflow:metadata-of-output-with-log; >> ]; >> . >> >> >> >> >> -Tim >> >> >> >> >> >> --Stephan >> >> >> >> >> >> >> -- >> 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 > > > > -- > Dr Simon Miles > Lecturer, Department of Informatics > Kings College London, WC2R 2LS, UK > +44 (0)20 7848 1166 > > Provenance: The Bridge Between Experiments and Data: > http://eprints.dcs.kcl.ac.uk/1372/ > >
Received on Wednesday, 21 December 2011 18:13:29 UTC