Re: PROV-ISSUE-64 (definition-use): definition of use [Conceptual Model]

Hi Simon,

I am in agreement.  Paolo and I discussed the idea
of distinguishing role type from role name (like parameter name and 
parameter type).
Uniqueness property applies to role name, not to role type.

One of the reasons for the uniqueness property is the ability to replay 
executions.
You need to be able to know which value to  "plug" to which input/port.

Currently, all the constraints and definitions pertaining to roles in the
specification are about role names.

One might argue that role types could be found in the process execution 
specific
ontology that declares role names.  Alternatively, we can make them 
explicit in PIL.

Views on this?

Regards,
Luc


On 04/08/11 16:00, Simon Miles wrote:
> Hi Luc,
>
> Reading Graham's comment I'm also unclear what the purpose of this
> requirement is.
>
> I have a suspicion that the lack of clarity could from the conflation
> of two issues:
>
> 1. the desire to express the role played by bobs in executions
> 2. the desire to have uniquely named parameters for executions, so
> that bobs used can be uniquely referenced
>
> Maybe I'm wrong and this is not the problem at all. But if it is, then
> I suggest that we untangle the two issues. It is counter-intuitive to
> me, and I strongly suspect it would be to users of the standard, to
> disallow us from saying that two bobs played the same role in an
> execution. If I want to say that process P chose numbers randomly from
> two lists L1 and L2, then I would want to assert that L1 and L2 played
> the same role in P. There may well always be a difference in each
> bob's role if you look in fine detail at P, but I might not know that
> difference nor want to model it if I did.
>
> thanks,
> Simon
>
> On 4 August 2011 09:41, Graham Klyne<GK@ninebynine.org>  wrote:
>    
>> Luc Moreau wrote:
>>      
>>> Hi Graham,
>>>
>>> On 07/29/2011 10:13 AM, Provenance Working Group Issue Tracker wrote:
>>>        
>>>> [[
>>>> A reference to a given BOB may appear in multiple use assertions that
>>>> refer to a given process execution, but each of those use assertions
>>>> must have a distinct role.
>>>> ]]
>>>> In light of the above, this seems nonsensical to me.
>>>>
>>>>
>>>>          
>>>
>>> I am trying to understand what the issue is.
>>>
>>> We're trying to say:
>>>
>>> For any b, bob(b,[...])
>>> For any pe, processExecution(pe)
>>>
>>>      for any two assertions use(pe,b,r1,t1) and use(pe,b,r2,t2), then
>>>       r1<>  r2
>>>
>>> Is there a problem with this?
>>>        
>> I now understand what you are trying to express.
>>
>> Is there a problem?  I don't know, because I don't properly understand what
>> purpose "role" is serving here.
>>
>> Does anything actually break if this requirement is dropped?  I.e. if it's OK to
>> say:
>>
>>    use(pe,b,r1,t1)
>> AND
>>    use(pe,b,r1,t2)
>>
>> #g
>>
>>
>>
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>>      
>
>
>    

Received on Thursday, 4 August 2011 20:24:46 UTC