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Re: Changes to prov:Dictionary

From: Timothy Lebo <lebot@rpi.edu>
Date: Wed, 6 Jun 2012 16:26:40 -0400
Cc: Stephan Zednik <zednis@rpi.edu>, Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>, "public-prov-wg@w3.org WG" <public-prov-wg@w3.org>
Message-Id: <07453476-068A-406B-BEE6-6F42CB3C372B@rpi.edu>
To: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Luc,

On Jun 6, 2012, at 2:36 PM, Luc Moreau wrote:

> 
> Hi all,
> 
> I dont understand this discussion.
> 
> See example 50
> http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-dm.html#example_50

http://aquarius.tw.rpi.edu/prov-wg/prov-o#derivedByInsertionFrom
has a prov-o example very similar to #example_50.

> We explicit list the contents of a dictionary after some insertion.

I agree with this example, what does it show that is wrong with prov-o?


> 
> Definition 38 in prov-constraints define membership
> http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-constraints.html#membership-as-insertion

Great.

> 
> Disallowing complete membership seems to go against the definition of insertion.

How so?
"Insertion is a derivation that transforms a dictionary into another, by insertion of one or more key-entity pairs."



> Are you suggesting that we don't exactly know what is being inserted in a dictionary?

No, we know _exactly_ what is inserted into the dictionary. They inserted KeyValuePairs are listed right in the assertion.


What we're saying is that for any prov:Dictionary and for any N known members, there is no way to know if that prov:Dictionary only has N members, or if there are more.

Membership is alive and healthy in this last PROV-O update announced in this thread.

What is being proposed is that the class prov:CompleteDictionary (and DM's optional "complete" attribute)  be removed from PROV.


-Tim



> 
> 
> 
> Professor Luc Moreau
> Electronics and Computer Science
> University of Southampton 
> Southampton SO17 1BJ
> United Kingdom
> 
> On 6 Jun 2012, at 17:05, "Stephan Zednik" <zednis@rpi.edu> wrote:
> 
>> 
>> On Jun 6, 2012, at 10:57 AM, Timothy Lebo wrote:
>> 
>>> Stian,
>>> 
>>> On Jun 6, 2012, at 10:39 AM, Stian Soiland-Reyes wrote:
>>> 
>>>> Without EmptyCollection or CompleteMembership the
>>>> collections/dictionaries are of almost no worth to my use cases,
>>> 
>>> EmptyCollection remains in the latest PROV-O (so that is not an issue).
>>> 
>>> It was CompleteMembership that got the ax (this is the topic at hand).
>>> 
>>> Regarding your use cases, I think it's important to cite Graham's points about uses cases for standards:
>>> http://www.w3.org/mid/4FCEFCB0.4090100@zoo.ox.ac.uk
>> 
>> +1 to the relevance of Graham's point about scope creep and system use cases vs. coverage/scope of a standard.
>> 
>>> 
>>> 
>>> 
>>>> as
>>>> all I can say then is that "some of the members are X, Y and Z" - but
>>>> there might also be A, B and C.
>> 
>> Are you specifically worried about the possibility that other members may be asserted at a later time by someone else?  If this is an issue than perhaps you could use a system-specific extension of prov:Collection which utilizes a terminated ordered list.
>> 
>> I must reiterate my agreement with Graham's point above that this need from this use case should not become a requirement for all collections defined in the standard.
>> 
>>>> In Taverna workflows, all collections
>>>> are closed (unless you export provenance before a workflow has
>>>> finished). It is important to know that ALL these genes - and no other
>>>> genes - came back. Just saying "some of these came back" is of less
>>>> value.
>>> 
>>> Would this use case be handled if Taverna instead leveraged the "additional attributes" that DM already provides?
>>> 
>>> memberOf(id; c, {(key_1, e_1), ..., (key_n, e_n)}, cplt, attrs)
>>> 
>>> perhaps a property taverna:isComplete or class taverna:CompleteDictionary ?
>> 
>> Even if this attribute was added to the prov or an extension of prov, it does not enforce the closed-world membership that Stian would like to have.
>> 
>> No attribute or class specialization will resolve the issue of trying to enforce CWA in RDF.
>> 
>>> 
>>>> 
>>>> 
>>>> I understand that in RDF if we don't use rdf:List, then statements of
>>>> such completeness are still fairly vague as the lists are not
>>>> terminated and additional tuples could be adding
>>>> members/insertions/removals.
>>> 
>>> If this can't be handled soundly and properly in PROV-O and OWA, then I don't think we should try (or, fake it).
>> 
>> +1
>> 
>> I think in general the idea of 'completeness' is incompatible with OWA and should not be addressed in PROV-O.
>> 
>> --Stephan
>> 
>>> 
>>>> 
>>>> However when I make a provenance export of a workflow run, I would
>>>> want to also say something like "These are all the workflow processes
>>>> that ran, and these are all the entities that were created".
>>> 
>>> 
>>> 
>>>> But
>>>> perhaps a more general completeness-claim for an account/bundle is out
>>>> of scope for PROV.
>>> 
>>> That seems to be the predominant perspective, as people have indicated in various email threads and tracker issues.
>>> With the use of a custom attribute and type ( taverna:isComplete or class taverna:CompleteDictionary ), can you accept removing the special optional parameter on DM's memberOf?
>>> 
>>>> 
>>>> 
>>>> However, I still don't undertstand what is the problem with saying
>>>> something is an empty collection.
>>> 
>>> Not an issue. EmptyDictionary is still in there :-)
>>> 
>>> Thanks!
>>> Tim
>>> 
>>>> 
>>>> On Wed, Jun 6, 2012 at 2:49 PM, Luc Moreau <L.Moreau@ecs.soton.ac.uk> wrote:
>>>>> 
>>>>> Hi Tim,
>>>>> 
>>>>> It's specifically your last point. Being to express whether membership was complete
>>>>> was a request from Stian and Paolo I believe.
>>>>> 
>>>>> Luc
>>>>> 
>>>>> 
>>>>> On 06/06/2012 02:31 PM, Timothy Lebo wrote:
>>>>> 
>>>>> Luc,
>>>>> 
>>>>> On Jun 6, 2012, at 12:48 AM, Luc Moreau wrote:
>>>>> 
>>>>> 
>>>>> 
>>>>> On 5 Jun 2012, at 23:18, "Timothy Lebo" <lebot@rpi.edu> wrote:
>>>>> 
>>>>> prov-wg (and prov-dm editors),
>>>>> 
>>>>> I've reviewed all of the materials (that I can find) regarding collective concerns about prov:Dictionary, and
>>>>> have committed changes to the latest PROV-O owl and html to address those concerns:
>>>>> 
>>>>> * https://dvcs.w3.org/hg/prov/raw-file/default/ontology/Overview.html
>>>>> * http://dvcs.w3.org/hg/prov/raw-file/default/ontology/ProvenanceOntology.owl
>>>>> 
>>>>> The changes are summarized here:
>>>>> 
>>>>> http://www.w3.org/2011/prov/wiki/index.php?title=Eg-34-us-supreme-court-membership&oldid=7905#PROV-O_changes_made.2C_inspired_by_this_example
>>>>> 
>>>>> and repeated here:
>>>>> 
>>>>>  Added class prov:Collection, as subclass of Entity
>>>>> Added property prov:hadMember domain prov:Collection range prov:Entity.
>>>>> 
>>>>> This supports both generic "simple set" prov:Collection and prov:Dictionary.
>>>>> 
>>>>> Made KeyValuePair a subclass of Entity
>>>>> 
>>>>> this follows from Set Collection :c prov:hadMember :my_member and the definition of Collection "A collection is an entity that has some members. The members are themselves entities").
>>>>> 
>>>>> Renamed prov:membership to prov:qualifiedMembership to follow qualification pattern naming.
>>>>> prov:Membership became subclass of prov:EntityInvolvement (though, it could become subclass of prov:KeyValuePairInvolvement, itself a subclass of prov:EntityInvolvement. But we'll try to simplify and reuse prov:entity)
>>>>> prov:member renamed to prov:pair and became a subproperty of prov:involvee
>>>>> Added property chain (qualifiedMembership o prov:pair) rdfs:subClassOf prov:hadMember
>>>>> Added prov:removed domain prov:Removal range prov:KeyValuePair
>>>>> Removed prov:CompleteDictionary from DM and PROV-O.
>>>>> 
>>>>> Why?
>>>>> Luc
>>>>> 
>>>>> 
>>>>> 
>>>>> What in particular would you like to discuss.
>>>>> As I said, this reflects a response to many concerns that have been raised by many people in many forms.
>>>>> In an effort to maintain focus and to make progress, I recommend that these points, the latest prov-dm, and the latest prov-o update serve as the basis for these discussions.
>>>>> 
>>>>> -Tim
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> You'll notice the prov-o modeling of Dictionaries is not consistent with latest prov-dm.
>>>>> 
>>>>> The prov-o team would like to ask the prov-dm editors to reconsider how collections and dictionaries are defined, so that they reflect the latest prov-o modeling of the PROV concepts.
>>>>> 
>>>>> Regards,
>>>>> Tim Lebo
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> cc tracker ISSUE-374 ISSUE-391
>>>>> 
>>>>> 
>>>>> 
>>>>> --
>>>>> 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
>>>> 
>>>> 
>>>> 
>>>> 
>>>> --
>>>> Stian Soiland-Reyes, myGrid team
>>>> School of Computer Science
>>>> The University of Manchester
>>>> 
>>>> 
>>> 
>> 
Received on Wednesday, 6 June 2012 20:27:42 UTC

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