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Re: Primer first draft for review

From: Simon Miles <simon.miles@kcl.ac.uk>
Date: Thu, 17 Nov 2011 13:26:19 +0000
Message-ID: <CAKc1nHe5R3_jYC3veBg5-_JkWjPOxV6jHqj_uavgyAyQ7xreFQ@mail.gmail.com>
To: Provenance Working Group WG <public-prov-wg@w3.org>
Hi Graham,

Thanks very much for the review, very helpful. I'll talk them through
with Yolanda, but have quick follow-ups for a couple.

Could you raise the complementarity (Section 2.7) question as a formal
issue? Stian made a similar point in private, and I suggest it would
be better to discuss this properly on a separate thread.

I think Luc separately answered the derivation points better than I
could. The primer will need to be aligned with the DM when the latter
is updated, and we can then come back to whether the primer explains
the idea adequately.

I'd welcome suggestions on how to give a non-technical intuition of
the difference between activity and entity. Endurant/perdurant seems
rather opaque language as you say, while "instantaneous" sounds wrong
to me for describing something that can persist and be asserted about
over time, and "ongoing" implies the activity has not ended.

Thanks,
Simon

On 17 November 2011 10:40, Graham Klyne <GK@ninebynine.org> wrote:
> On 15/11/2011 14:06, Simon Miles wrote:
>  > The first draft of the primer document is ready for the WG to read and
>  > start raising issues against. It would be particularly helpful to know
>  > if the general approach/structure is one that makes sense to others.
>
> Reviewing: http://dvcs.w3.org/hg/prov/raw-file/default/primer/Primer.html
>
> Generally, I think this document is very nicely done.  The text is crisp and to
> the point, and the examples are well chosen and well-introduced.  I recognize
> there's more to do, but it's a great start.  I think it's probably worth pushing
> for an early FPWD because I think it well help external reviewers to understand
> the more technical aspects of the model.  It helped me :)
>
> What follows are some relatively minor comments...
>
> ...
>
> 1. Introduction
>
> Para 1: the primer is not *only* about PROV-DM; it is also about representation
> in RDF using PROV-O-defined terms.  The examples cannot be derived from PROV-DM
> alone.
>
> 2.1 Entities
>
> I think this doesn't really capture the relationship between entities and things
> that may change, which is a key motivator for introducing the notion of
> "Entities".  Cf.
> http://dvcs.w3.org/hg/prov/raw-file/tip/paq/provenance-access.html#provenance--entities-and-resources
> for possible adaptable text (though in this context you may prefer to avoid the
> dependence on Web resources.)
>
> Properties/attributes used interchangeably: maybe just use "attributes"?
>
> 2.2 Activities
>
> "While entities are static aspects in the world" - I think it's not the "static"
> aspect that's key here.  Philosophically, this is the endurant/perdurant
> (continuant/occurrent) distinction, but that language probably doesn't help
> here.  Instead of static/dynamic, suggest instantaneous/ongoing.
>
> 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.)
>
> 2.8 Derivation
>
> I find it is relatively hard to extract the intended meaning of the different
> derivation terms from this.  I think expanding the final paragraph to state the
> aspect illustrated by the referenced examples would help.  e.g.
>
> "In PROV-DM terms, we say that the page in the browser was eventually derived
> from the sketch, in that a different sketch would have resulted in a different
> web page"
>
> <PROV-DM issue>
> I have never been particularly comfortable with this attempt to capture the
> distinction between something that was merely involved and something that
> actively informed the resulting entity.  Philosophically, I think it's a very
> tricky distinction to draw.  Also, it draws us into discussion of what might
> have been, which is something I understand that provenance is not intended to
> capture.
>
> In the primer example given about "DRAFT FOR REVIEW", maybe its presence does
> have an effect on the eventual document; if it were not present, the document
> might have been published without further revision.  Who knows?  I think there
> may be cases where the form of contribution is clearer and testable (e.g.
> becamePartOf),  but to simply distinguish between contributory and
> non-contributory derivation is, I think, rather hard to do.
>
> My suggestion would be to drop the distinction, but to allow applications to
> specialize the property in ways that make sense for the application.
> </PROV-DM issue>
>
> Back to the primer:  I find that the distinction between eventuallyDeriuvedFrom
> and DerivedFrom is unclear.  I see two possible readings:
> (a) derivedFrom indicates the activity by which derivation occurred, but
> eventuallyDerivedFrom does not
> (b) derivedFrom is an account-dependent direct derivation by some activity
> (possibly unspecified) - (hence non-transitive), and eventuallyDerivedFrom is
> account-independent, transitive, possibly-indirect derivation.
>
> <PROV-DM issue>
> Is it possible to state that there is a direct derivation relation between two
> entities by some unspecified (existentially quantified) process execution?
> </PROV-DM issue>
>
> Hmmm... I'm finding the three cases in the primer don't seem to align with the
> current PROV-DM
> (http://dvcs.w3.org/hg/prov/raw-file/tip/model/ProvenanceModel.html#Derivation-Relation)
>
> ...
>
> #g
> --
>
>
> On 15/11/2011 14:06, Simon Miles wrote:
>> Hello all,
>>
>> The first draft of the primer document is ready for the WG to read and
>> start raising issues against. It would be particularly helpful to know
>> if the general approach/structure is one that makes sense to others.
>>
>> http://dvcs.w3.org/hg/prov/raw-file/default/primer/Primer.html
>>
>> It covers a subset of PROV-DM/-O that we thought was stable enough to
>> explain and illustrate, and is definitely work in progress. It has
>> PROV-O examples only, but we have asked Paolo to start considering ASN
>> translations now this draft is out.
>>
>> Thanks in particular to Stephan and Stian for substantial efforts on
>> the content of this draft (in addition to those of Yolanda and myself
>> as editors).
>>
>> Thanks,
>> Simon
>>
>



-- 
Dr Simon Miles
Lecturer, Department of Informatics
Kings College London, WC2R 2LS, UK
+44 (0)20 7848 1166

Provenance-based Validation of E-Science Experiments:
http://eprints.dcs.kcl.ac.uk/1268/
Received on Thursday, 17 November 2011 13:54:15 UTC

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