- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Mon, 25 Jul 2011 11:05:22 +0100
- To: public-prov-wg@w3.org
On 07/25/2011 10:52 AM, Paul Groth wrote: > Ok... and the justification for this is that it makes the data > structure uniform....? Yes > > It seems that this unspecified role will have some kind of special > semantics, no? > It's a default role for asserters who don't assert a specific role. Luc > Paul > > Luc Moreau wrote: >> Remember that I suggested concrete representations have the >> opportunity to >> offer role-less convenience syntax (as a kind of "macro" that expands >> into a construct >> with a role "unspecified"). >> >> Using the notation in the spec: >> use(pe,e) expands to use(pe,e,unspecifiedRole) >> where unspecifiedRole is a distinguished role. >> >> Isn't your requirement about "easy writing"? I believe an appropriate >> choice of syntax addresses this requirement. >> >> Luc >> >> >> On 07/25/2011 10:35 AM, Paul Groth wrote: >>> I'm using the definitions in [1], which are used in W3C specs. The >>> definitions for MUST and SHOULD are: >>> >>> - MUST This word, or the terms "REQUIRED" or "SHALL", mean that the >>> definition is an absolute requirement of the specification. >>> >>> - SHOULD This word, or the adjective "RECOMMENDED", mean that there >>> may exist valid reasons in particular circumstances to ignore a >>> particular item, but the full implications must be understood and >>> carefully weighed before choosing a different course. >>> >>> >>> The justification for using SHOULD is that it allows me some >>> flexibility in writing down provenance that is compatible with the >>> spec. If I don't know the roles and I won't break anything but I might >>> not get the full functionality of the spec (maybe?). So I think that >>> there are valid reasons not to write down roles but probably I should >>> think before not doing it. >>> >>> cheers, >>> Paul >>> >>> >>> [1] http://www.ietf.org/rfc/rfc2119.txt >>> >>> Luc Moreau wrote: >>>> It would be good to have advise on the choice MUST/SHOULD. >>>> >>>> I would have thought that to promote interoperability we should go for >>>> the stronger requirements, >>>> when possible. >>>> >>>> I can turn your comment around. I'm missing a justification for a >>>> SHOULD >>>> here. >>>> >>>> Luc >>>> >>>> >>>> PS. I don't think it's a hack to have unspecified role. Mandating a >>>> role >>>> guarantees a uniform data structure. >>>> It facilitates the writing of queries/searches. I guess >>>> that's my >>>> justification for MUST. >>>> >>>> >>>> On 07/25/2011 10:22 AM, Paul Groth wrote: >>>>> It seems like unspecified is a hack to let you get around not >>>>> saying a >>>>> role. >>>>> >>>>> Again, I think I'm missing a justification of the MUST verses just >>>>> making it a strong recommendation (i.e. SHOULD). >>>>> >>>>> I think you have some inferences in mind based around roles.... but I >>>>> think it just means that you won't be able to make those >>>>> inferences if >>>>> you don't provide roles. >>>>> >>>>> thanks, >>>>> Paul >>>>> >>>>> Luc Moreau wrote: >>>>>> I believe there is a difference between a conceptual model and its >>>>>> encoding in >>>>>> a specific data/knowledge format. >>>>>> >>>>>> In my view, it is reasonable to require the presence of a role in a >>>>>> conceptual model. >>>>>> A given notation, say RDF, may provide "abbreviations", which allow >>>>>> for >>>>>> the role not >>>>>> to be expressed. This notation will have an explanation that >>>>>> absence of >>>>>> a role corresponds >>>>>> to the role "unspecified". >>>>>> >>>>>> So, I believe that the conceptual model should define distinguished >>>>>> roles, e.g. unspecified. >>>>>> >>>>>> BTW, the file note.txt in the repository also suggested other roles >>>>>> >>>>>> Luc >>>>>> >>>>>> >>>>>> >>>>>> On 07/23/2011 03:14 PM, Provenance Working Group Issue Tracker >>>>>> wrote: >>>>>>> PROV-ISSUE-40 (recommended-roles): Roles should not be SHOULD and >>>>>>> not MUST [Conceptual Model] >>>>>>> >>>>>>> http://www.w3.org/2011/prov/track/issues/40 >>>>>>> >>>>>>> Raised by: Paul Groth >>>>>>> On product: Conceptual Model >>>>>>> >>>>>>> Currently, roles are required for Generation, Use, and >>>>>>> isControlledby. >>>>>>> >>>>>>> Specifically the following sentence is given: >>>>>>> >>>>>>> "Use, Generation, and Control assertions must contain a role." >>>>>>> >>>>>>> It is not clear why roles must always be there. In some cases, I >>>>>>> may >>>>>>> not want to assert the role that something played with respect to a >>>>>>> process. >>>>>>> >>>>>>> Suggested resolution is to replace MUST with SHOULD. >>>>>>> >>>>>>> >>>>>>> >>>>>>> >> > -- 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 10:05:58 UTC