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Re: PROV-ISSUE-153 (complementarity): Complementarity description differs from model definition [Primer]

From: Graham Klyne <GK@ninebynine.org>
Date: Tue, 22 Nov 2011 11:46:24 +0000
Message-ID: <4ECB8B90.5090306@ninebynine.org>
To: public-prov-wg@w3.org

(hurried response)

I think what you say is True.  But Primer says (or said):

In PROV-DM, we say there is complementarity between one entity and another if 
everything that characterizes the second is also true of the first.

My point was that this is not aligned with PROV-DM.

But I happen to think it's a more useful property to define (modulo name) - and 
as stated above is clearly transitive.


On 21/11/2011 21:10, Simon Miles wrote:
> Hello Graham,
> I don't think either the complementarity concept in Prov-DM or the
> wasComplementOf relation in Prov-O are symmetric are they? The Prov-DM
> description of complementarity specifically includes "In the
> particular case where the set P of attributes of B is a strict
> superset of A's attributes, then we say that B is-complement-of A, but
> in this case the opposite does not hold." If complementarity is
> asymmetric in any case, then it is an asymmetric relation in general.
> The Prov-O wasComplementOf relation has a direction and it isn't said
> to imply the inverse.
> More importantly, the primer intuition section should not try to cover
> all the possible cases or make normative statements, but illuminate
> the key idea with a simple example. I believe the key idea of
> complementarity is that two entities may be perspectives on the same
> thing, and I think the first paragraph does describe this key idea.
> The second paragraph in the primer is then a more detailed example,
> using the asymmetric case. I agree that complementarity is not
> necessarily asymmetric, but I think that case is the easiest to
> briefly explain why prov:wasComplementOf has direction in the worked
> example.
> I'm open to suggestions on how to be clearer and more complete in this
> section as long as we keep it non-technical.
> Thanks,
> Simon
> On 18 November 2011 09:17, Provenance Working Group Issue Tracker
> <sysbot+tracker@w3.org>  wrote:
>> PROV-ISSUE-153 (complementarity): Complementarity description differs from model definition [Primer]
>> http://www.w3.org/2011/prov/track/issues/153
>> Raised by: Graham Klyne
>> On product: Primer
>> Primer section: 2.7 Complementarity
>> While I personally think the notion of complementarity described here is the
>> more useful one, I don't think it agrees with the current PROV-DM
>> (http://dvcs.w3.org/hg/prov/raw-file/tip/model/ProvenanceModel.html#record-complement-of).
>> (What you describe here might be termed "characterizationOf" (of "viewOf"),
>> which notion I see as being foundational to the way entities are related to
>> things.)
>> To clarify: in my reading, primer defines complementarity as an asymmetric relationship, where one characterization is subsumed by the other.  But the model definition is symmetric,  simply saying that the characterizations overlap in some sense.
Received on Tuesday, 22 November 2011 11:50:19 UTC

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