Re: updates to PAQ doc for discussion

Khalid Belhajjame wrote:
> 
> Graham,
> 
> I wasn't thinking of Sparql, rather I was more referring to the 
> definitions. To me IVPof impose an additional constraint compared with 
> complement of, and therefore, is less general.

I appreciate that - I was using SPARQL as an example of how the inference might 
be used practically given the alternative definition.

#g
--

> On 19/08/2011 12:22, Graham Klyne wrote:
>> I too find the name unhelpful.  But I'm also concerned about the form 
>> of the definition.  I'm not sure "generality" is the right aspect, 
>> though, as in some ways I see IVPof (to use the old name) as being 
>> more general than complementOf.
>>
>> Why:
>>
>> Roughly, using SPARQL, I can use IVPof to locate instances of 
>> complementOf.  But I can't see how to do the other way.
>>
>> e.g.
>>
>> [[
>> CONSTRUCT
>>    { ?v1 complementOf ?v2 }
>> WHERE
>>    { ?v1 IVPof ?r ; ?v2 IVPof ?r }
>> ]]
>>
>> So from this operational perspective, IVPof is more generally applicable.
>>
>> (But from another perspective, this is possible because IVPof is more 
>> constraining - less general - that complementOf.  Hence my comment 
>> about generality not necessarily being a helpful criterion.)
>>
>> I find that when I think about provenance being related to an 
>> invariant or less variant view of a resource (e.g. see the discussion 
>> at 
>> http://dvcs.w3.org/hg/prov/raw-file/tip/paq/provenance-access.html#provenance--context-and-resources), 
>> the notion of IVP is useful.  I have not yet found a case where 
>> talking/thinking about complementOf is useful to me.  Fior this 
>> reason, I prefer having IVPof (or viewOf, or some other name) to 
>> complementOf.
>>
>> #g
>> -- 
>>
>>
>> Myers, Jim wrote:
>>> I'm complaining about the name 'complement' not the generality of the 
>>> definition. Complementary angles are not different characterizations 
>>> of the same angle, they are different angles that create a whole. A 
>>> wine complements food. Some other term with the broader definition 
>>> would be fine. (BTW: I am beginning to think that being able to 
>>> associate a time interval with the relationship would be useful...)
>>>
>>>  Jim
>>>
>>>
>>>> -----Original Message-----
>>>> From: Khalid Belhajjame [mailto:Khalid.Belhajjame@cs.man.ac.uk]
>>>> Sent: Wednesday, August 17, 2011 1:31 PM
>>>> To: Myers, Jim
>>>> Cc: Paul Groth; Graham Klyne; public-prov-wg@w3.org
>>>> Subject: Re: updates to PAQ doc for discussion
>>>>
>>>> Hi Jim
>>>>
>>>> On 16/08/2011 13:45, Myers, Jim wrote:
>>>>> As for complementOf - since complement means 'counterpart' and has the
>>>> notion of not being the same thing - being separate and adding to 
>>>> the thing, I
>>>> don't think it works as a replacement for IVPof - viewOf doesn't 
>>>> capture
>>>> everything but would be better than complement in that its English 
>>>> meaning
>>>> does not conflict ...
>>>>
>>>> I am not sure I understand what you mean. Could you please elaborate?
>>>>
>>>> The way is complement of is defined seems to me more general that 
>>>> IVP of and
>>>> also more natural. While IVPof requires that all the immutable 
>>>> attributes of
>>>> one characterization are subset of the immutable attributes of the 
>>>> other
>>>> characterization, isComplementOf does not pose this constraint, 
>>>> which is
>>>> plausible: in practice, when we have two characterizations of an 
>>>> entity, these
>>>> characterizations are likely to use different set of attributes 
>>>> depending on the
>>>> observer, and the likelihood that the immutable attributes of one 
>>>> are subset of
>>>> the immutable attributes of the second is small.
>>>>
>>>> Khalid
>>>>
>>>>
>>>>
>>>>>   Jim
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Paul Groth [mailto:p.t.groth@vu.nl]
>>>>>> Sent: Tuesday, August 16, 2011 1:21 AM
>>>>>> To: Myers, Jim
>>>>>> Cc: Graham Klyne; public-prov-wg@w3.org
>>>>>> Subject: Re: updates to PAQ doc for discussion
>>>>>>
>>>>>> Hi Jim
>>>>>>
>>>>>> I think<link>  elements in PAQ serve a different purpose the
>>>>>> semantics is here's how you find me (the resource)  in provenance
>>>> information.
>>>>>> ComplementOf has a much more constrained meaning.
>>>>>>
>>>>>> Paul
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Aug 16, 2011, at 3:01, "Myers, Jim"<MYERSJ4@rpi.edu>  wrote:
>>>>>>
>>>>>>> But, having introduced the definition in this way, other uses are
>>>>>>> possible.  The example I've started thinking about is that multiple
>>>>>>> <link>  elements might indicate different URIs denoting different
>>>>>>> levels of
>>>>>> invariance.
>>>>>>> - why aren't these just IVPof relationships? (I'm not arguing
>>>>>>> against encoding pil relationships as links, just against adding 
>>>>>>> a 'target'
>>>>>>> concept that duplicates other relationships in the model.)
>>>>>>>
>>>>>>> Jim
>>>>>>> ________________________________________
>>>>>>> From: Graham Klyne [graham.klyne@zoo.ox.ac.uk]
>>>>>>> Sent: Monday, August 15, 2011 5:38 PM
>>>>>>> To: Myers, Jim
>>>>>>> Cc: Paul Groth; public-prov-wg@w3.org
>>>>>>> Subject: Re: updates to PAQ doc for discussion
>>>>>>>
>>>>>>> Myers, Jim wrote:
>>>>>>>>> In Issue 46 (http://www.w3.org/2011/prov/track/issues/46), Luc
>>>>>>>>> raised the point that the scenario we had agreed to address
>>>>>>>>> included a case where the recipient of a resource representation
>>>>>>>>> had no way to know its URI for the purposes of provenance
>>>>>>>>> discovery.  After short discussion, my response to this issue was
>>>>>>>>> to introduce a new link relation type (currently called "target")
>>>>>>>>> to allow this URI to be encoded
>>>>>> in the header of an HTML document.
>>>>>>>>> Does this help?
>>>>>>>> So this is only used inside an HTML entity?
>>>>>>> That was the compelling use-case, but once defined, other uses are
>>>>>>> not
>>>>>> excluded.
>>>>>>>> ... I.e. it is not a relationship between two entities, but is a
>>>>>>>> means to embed an identifier in an entity (for HTML)?
>>>>>>> Interesting take.  Practically, in the HTML use case, I think I'd 
>>>>>>> have to
>>>> agree.
>>>>>>> But I think it is still technically a relation in the same way that
>>>>>>> owl:sameAs is a relation, even though its semantics tell us that the
>>>>>>> related RDF nodes denote the same thing.  Like all HTML<link>
>>>>>>> elements, it defines a relation between the resource of which the
>>>>>>> containing document is a representation and a resource denoted by
>>>>>>> the given
>>>>>> URI.  They may both be the same resource.
>>>>>>> But, having introduced the definition in this way, other uses are
>>>>>>> possible.  The example I've started thinking about is that multiple
>>>>>>> <link>  elements might indicate different URIs denoting different
>>>>>>> levels of invariance.  If the HTML is a document in a source code
>>>>>>> management system, one such URI might denote a specific version, and
>>>>>>> another might denote the "current" version, both of which might
>>>>>>> reasonably
>>>>>> be the referent for provenance assertions.
>>>>>>> These other uses are not reasons that the propoal was introduced,
>>>>>>> but are just consequences of not placing unnecessary constraints on
>>>>>>> the use of the existing<link>  feature as defined.
>>>>>>>
>>>>>>>> An "ID card" mechanism that would allow me to keep my rdf:resource
>>>>>>>> URL
>>>>>> on my physical body so you could connect me to my online identity is
>>>>>> the same type of thing?
>>>>>>> Hmmm... I suppose you might think of it like that, but I'm wary of
>>>>>>> adopting that view as it tends to arbitrarily exclude other
>>>>>>> possibilities that arguably should flow from this use of 
>>>>>>> the<link>  element.
>>>>>>>
>>>>>>> #g
>>>>>>> -- 
>>>>>>>
>>>>>>>
>>>
>>>
>>
>>
> 

Received on Monday, 22 August 2011 09:48:50 UTC