Re: PROV-ISSUE-411 (tracedto-inference): Should tracedTo allow tracing across specialization relation [prov-dm-constraints]

Hi,

I guess what I am saying is that I don't have a particular intuition for what tracedTo means.  To me it is just a (more or less ad hoc) transitive closure query over the other edges to link things together.  If people think specialization should be included in the transitive closure then that seems fine, given that there seems to be general agreement that tracedTo is useful.  To play devil's advocate, if we add (and standardize) more inferences, then we can't undo this later.

One could argue that given 

specializationOf(bbcsiteToday, bbcsite2012)
wasAttributedTo(bbcsite2012,bbc)

It seems reasonable to infer 

wasAttributedTo(bbcsiteToday,bbc)

from which the tracedTo would follow, without directly inferring tracedTo from specialization.  In general, we should consider how specialization and alternate may interact with other relations - at present there are no constraints or inferences about this.

--James

On Jun 20, 2012, at 5:43 PM, Luc Moreau wrote:

> hi James
> 
> If we have:
> 
> specializationOf(bbcsiteToday, bbcsite2012)
> wasAttributed(bbcsite2012,bbc)
> 
> wouldn't we want to infer tracedTo(bbcsiteToday, bbc)?
> 
> Luc
> On 20/06/2012 15:55, James Cheney wrote:
>> 
>> 
>> On Jun 19, 2012, at 2:41 PM, Khalid Belhajjame wrote:
>> 
>>> 
>>> 
>>> On 19 June 2012 21:10, Provenance Working Group Issue Tracker <sysbot+tracker@w3.org> wrote:
>>> PROV-ISSUE-411 (tracedto-inference): Should tracedTo allow tracing across specialization relation [prov-dm-constraints]
>>> 
>>> http://www.w3.org/2011/prov/track/issues/411
>>> 
>>> Raised by: Luc Moreau
>>> On product: prov-dm-constraints
>>> 
>>> Hi
>>> 
>>> The constraints document allows for tracedTo to be inferred from derivation and attribution. Should the following also hold:
>>> 
>>> specialization(e2,e1)
>>> implies
>>> tracedTo(e2,e1)
>>> 
>>> 
>>> I didn't think about this hard, but my first guess is that traceability should be reserved to entities that are (transitively) related through activities. This does not necessarily apply to specialization: an entity e2 that is a specialization of another entity e1, can be created independently of e1.
>> 
>> I also don't see a strong motivation for this inference, since specialization is more of a "part of" relationship - to me it doesn't seem sensible to say "the BBC web site today" is  "derived from" or "traced to" "the BBC web site during 2012".  
>> 
>> But then, tracedTo is essentially building-in one specific (likely useful, but ad hoc) transitive "query" over the provenance, and nothing would break if we added this inference as far as I can tell (since there are no constraints that can be violated by adding tracedTo edges at the moment).
>> 
>> --James
>> 
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