Re: PROV-ISSUE-7 (define-derivation): Definition for Concept 'Derivation' [Provenance Terminology]

Hi,

 From the discussion so far on derivation it seems that most people tend 
to define derivation between resource states or resources state 
representations, but not for resources.

My take on this is that in a context where a resource is mutable, 
derivations will mainly be used to associate resource states and 
resource states representations.

That said, based on derivations connecting resource states and resources 
state representations, one can infer new derivations between resources. 
For example, consider the resource r_1 and the associated resource state 
r_1_s, and consider that r_1_s was used to construct a new resource 
state r_2_s, actually the first state, of the resource r2. We can state 
that r_2_s is derived from r_1_s, i.e., r_1_s -> r_2_s. We can also 
state that the resource r_2 is derived from the resource r_1, i.e., r_1 
-> r_2

PS: I added a defintiion of derivation within this lines to the wiki:
http://www.w3.org/2011/prov/wiki/ConceptDerivation

Thanks, khalid




On 01/06/2011 07:49, Luc Moreau wrote:
> Hi Graham,
>
> Isn't it that you used the duri scheme to name the two resource states 
> that exist in
> this scenario?
>
> In your view of the web, is there a notion of stateful resource? Does 
> it apply here?
>
> Thanks,
> Luc
>
>
>
> On 31/05/11 23:57, Graham Klyne wrote:
>> Luc Moreau wrote:
>>> Graham,
>>>
>>> In my example, I really mean for the two versions of the chart to be 
>>> available at
>>> the same URI. (So, definitely, an uncool URI!)
>>>
>>> In that case, there is a *single* resource, but it is stateful. 
>>> Hence, there
>>> are two *resource states*, one generated using (stats2), and the 
>>> other using (stats3).
>>
>> Luc,
>>
>> I had interpreted your scenario as using a common URI as you explain.
>>
>> But there are still several resources here, but they are not all 
>> exposed on the web or assigned URIs.  I'm appealing here to anything 
>> that *might* be identified as opposed to things that actually are 
>> assigned URIs.   (For example, the proposed duri: scheme might be 
>> used - http://tools.ietf.org/id/draft-masinter-dated-uri-07.html)
>>
>> (And the URI is perfectly "cool" if it is specifically intended to 
>> denote a dynamic resource.  A URI used to access the current weather 
>> in London can be stable if properly managed.)
>>
>> (I think this is all entirely consistent with my earlier stated 
>> positions.)
>>
>> #g
>> -- 
>>
>>> Of course, if blogger had used cool uris, then, c2s2 and c2s3 would 
>>> be different resources.
>>>
>>> Luc
>>>
>>> On 05/31/2011 02:25 PM, Graham Klyne wrote:
>>>> I see (at least) two resources associated with (c2):  one generated 
>>>> using (stats2), and other using (stats3).  We might call these 
>>>> (c2s2) and (c2s3). 
>>>
>
>