Re: PROV-ISSUE-45: isDerivedFrom and IVPof are transitive. [Conceptual Model]

Hi,

In the latest version of the document, you will find a proposal [1] that 
addresses
the issue of transitivity for derivation.  I copy the text below for 
convenience.



5.5.2 Transitivity

The relationship isDerivedFrom is transitive. Indeed, given 
isDerivedFrom(e2,e1) and isDerivedFrom(e1,e0), e2 is transformed from 
(resp. created from/affected by) e1, which in turn is transformed from 
(resp. created from/affected by) e0. So, e2 is indirectly transformed 
from (resp. created from/affected by) e0.

The relationship isDerivedFrom+ is the transitive closure of isDerivedFrom.

Whereas isDerivedFrom(e1,e0)is an assertion that corresponds to a single 
process execution, isDerivedFrom+(e1,e0) is obtained by transitive 
closure isDerivedFrom. In addition, this specification introduces a 
further assertion isDerivedFromInMultipleSteps(e1,e0), which may 
correspond to one or more process executions. The inference rule above 
cannot be used on this assertion, as the number of Process Executions 
involved in the derivation is not known.

Comments? Thoughts?

Best regards,
Paolo and Luc

[1] 
http://dvcs.w3.org/hg/prov/raw-file/default/model/ProvenanceModel.html#transitivity

On 07/25/2011 12:29 PM, Paolo Missier wrote:
> Khalid
>
> I don't think we have ever agreed on that, but I should really check 
> the voting history. The latest definition of IVP-of (or complement-of) 
> is sufficiently precise (i.e., algorithmic) that transitivity follows, 
> but derivation is purely asserted and as such there is no ground to 
> say that it is transitive -- unless we say axiomatically that it 
> should be.
>
> -Paolo
>
>> PROV-ISSUE-45: isDerivedFrom and IVPof are transitive. [Conceptual Model]
>>
>> http://www.w3.org/2011/prov/track/issues/45
>>
>> Raised by: Khalid Belhajjame
>> On product: Conceptual Model
>>
>>
>> If we agree that "isDerivedFrom" and "IVPof" are transitive, then I would suggest that this should be specified in the model working draft.
>>
>> khalid
>

-- 
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