W3C home > Mailing lists > Public > public-prov-wg@w3.org > January 2012

Re: PROV-ISSUE-180 (TLebo): defaults to prov:steps="n" causes issue in PROV-O [prov-dm]

From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Date: Mon, 16 Jan 2012 13:34:17 +0000
Message-ID: <EMEW3|187cf271f8245bcb2990e4416daa06ebo0FDYK08L.Moreau|ecs.soton.ac.uk|4F142759.3020004@ecs.soton.ac.uk>
To: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>
CC: public-prov-wg@w3.org
Hi Stian, Tim,

I have updated the derivation record section.

The case 'unknown' was not explained, and it should be clearer now.

As far as the number of steps are concerned, the attribute prov:steps 
can now take values single and any.

Does this help?
Cheers,
Luc

On 12/23/2011 08:55 PM, Stian Soiland-Reyes wrote:
>
> Sounds better, or even "single" and "unknown" - as the latter will 
> also include a single unknown activity. (otherwise, if we don't know 
> the activities, it would be hard to guarantee that it is minimum 2 steps)
>
> However the activities might be known, and even asserted, but the 
> account wanted to indicate the derivation across multiple activities 
> (as we don't yet have the concept of subactivities).. so something 
> similar to "unknown".. "undefined"?
>
> On Dec 22, 2011 1:42 AM, "Luc Moreau" <L.Moreau@ecs.soton.ac.uk 
> <mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
>
>     Hi Stian,
>     It's in prov-dm:
>     http://dvcs.w3.org/hg/prov/raw-file/default/model/ProvenanceModel.html#dfn-steps
>
>     Now, it it helps, we could use values 'single' and 'multiple'
>     instead of 1 and n (which
>     for the purpose of prov-dm were regarded as strings).
>
>     Luc
>
>     On 22/12/11 06:19, Stian Soiland-Reyes wrote:
>>
>>     it is a PROV-DM issue because it us not clear if the default
>>     applies to PROV-ASN or PROV-DM. From your statement in the below
>>     email it sounds like ASN, from text DM.
>>
>>     I personally find this attribute very confusing. It hints that
>>     steps=3 would be allowed, but only. values 1 and n are described.
>>     If this is really a boolean meaning "known to be single step"
>>     then I would think of something along those lines instead of
>>     pretending it is an integer.
>>
>>     (Note that we are also used to interpret n in x=n-1 as "insert
>>     your count here")
>>
>>     On Dec 20, 2011 10:45 AM, "Luc Moreau" <L.Moreau@ecs.soton.ac.uk
>>     <mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
>>
>>         Hi Tim,
>>
>>         How do you map prov:steps to prov-o?  Your mapping could
>>         require this property
>>         to be mandatory, and not rely on a default value.
>>
>>         Is this really a prov-dm issue?
>>
>>         Best regards,
>>         Luc
>>
>>         On 12/02/2011 07:28 PM, Provenance Working Group Issue
>>         Tracker wrote:
>>
>>             PROV-ISSUE-180 (TLebo): defaults to prov:steps="n" causes
>>             issue in PROV-O [prov-dm]
>>
>>             http://www.w3.org/2011/prov/track/issues/180
>>
>>             Raised by: Timothy Lebo
>>             On product: prov-dm
>>
>>             Imposing a "default" value for prov:steps will cause
>>             issues in PROV-O, which embraces the open world.
>>
>>             > From [1]:
>>
>>             "It is optional to include the attribute prov:steps in an
>>             imprecise-n derivation record. It defaults to
>>             prov:steps="n"."
>>
>>
>>             An OWL axiom such as "imprecise-n derivation records must
>>             have values of prov:step that are integers greater than
>>             1" can be done, and if an instance of Derivation is typed
>>             to "imprecise-n derivation record", then one knows that
>>             it has more than one step -- even when no prov:step has
>>             been asserted.
>>
>>
>>             If this OWL approach is taken, would we be violating the
>>             DM's "It defaults to prov:steps="n"."?
>>
>>             Thanks,
>>             Tim
>>
>>             [1]
>>             http://dvcs.w3.org/hg/prov/raw-file/tip/model/ProvenanceModel.html#Derivation-Relation
>>
>>
>>
>>
>>
>>         -- 
>>         Professor Luc Moreau
>>         Electronics and Computer Science   tel:   +44 23 8059 4487
>>         University of Southampton          fax:   +44 23 8059 2865
>>         Southampton SO17 1BJ               email:
>>         l.moreau@ecs.soton.ac.uk <mailto:l.moreau@ecs.soton.ac.uk>
>>         United Kingdom http://www.ecs.soton.ac.uk/~lavm
>>         <http://www.ecs.soton.ac.uk/%7Elavm>
>>
>>

-- 
Professor Luc Moreau
Electronics and Computer Science   tel:   +44 23 8059 4487
University of Southampton          fax:   +44 23 8059 2865
Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk
United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
Received on Monday, 16 January 2012 13:35:13 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 13:06:52 GMT