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Re: PROV-ISSUE-89 (what-entity-attributes): How do we find the attributes of an entity? [Formal Model]

From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Date: Thu, 08 Sep 2011 17:31:10 +0100
Message-ID: <EMEW3|9bec6f20b6208c34169d25b4e2f673a5n87HVF08L.Moreau|ecs.soton.ac.uk|4E68EDCE.9050406@ecs.soton.ac.uk>
To: Satya Sahoo <satya.sahoo@case.edu>
CC: public-prov-wg@w3.org
Hi Satya,

On 09/08/2011 05:16 PM, Satya Sahoo wrote:
> Hi Luc,
> My responses are interleaved:
>
> > "instance" indeed e.g.:  entity(e0, [ type: "File", location: 
> "/shared/crime.txt", creator: "Alice" ])
> ok
>
> > Using the Provenance Abstract Syntax Notation, I could assert two 
> entities (instances)
> > entity(e1,[ company: "Toyota", model: "Corolla"])
> > entity(e2,[ company: "Toyota", model: "Corolla", owner="tom"])
> The entity we are referring to is an instance of "Toyota Corolla car" 
> and its identifying attribute is "1a", which distinguishes this 
> instance from other instances of "Toyota Corolla car". As described in 
> my earlier mail, we first need to decide what are the "necessary" 
> attributes of an instance and depending on that we can enumerate them 
> for uniquely "identifying" that entity.
>
> So,
> entity(e1,[ company: "Toyota", model: "Corolla"]) should include 
> attribute "vehicle identification number" with value "1a".
>
> entity(e2,[ company: "Toyota", model: "Corolla", owner="tom"]) is the 
> same entity as e1, but with an additional (non-essential?) atribute of 
> ownership.
>
> e1 and e2 can exist, but it should be explicit that e2 is e1 with 
> additional "necessary" attributes.

Yes, sorry, I should have made the id explicit. So here they are:

entity(e1,[ company: "Toyota", model: "Corolla", identification="1a"])

entity(e2,[ company: "Toyota", model: "Corolla", identification="1a", 
owner="tom"])

entity(e3,[ company: "Toyota", model: "Corolla", identification="1a", 
owner="luc"])

In paticular, we may want to write

wasComplementOf(e2,e1)
wasComplementOf(e3,e1)

and also that

wasDerivedFrom(e3,e2)  (since e3 was bought by luc from tom)

>
>
> > How do I know the attributes of each entity: company/model for 
> e1 and company/model/owner for e2?
> I am not sure I completely understand the query - but we would follow 
> the attributes/property links associated with both e1 and e2 to 
> retrieve the appropriate values.
>

But how does it work in an open world context, when there may be other 
assertions in your triple
store, e.g. e1 hasColor blue.

But the color property is not one of the attributes  used in any of e1, 
e2, e3.

Luc

> Thanks.
>
> Best,
> Satya
>
> On Thu, Sep 8, 2011 at 10:30 AM, Luc Moreau <L.Moreau@ecs.soton.ac.uk 
> <mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
>
>     Hi Satya,
>
>     Responses interleaved
>
>
>     On 09/06/2011 06:26 PM, Satya Sahoo wrote:
>>     Hi Luc,
>>     To clarify a few points:
>>     1. In case of the provenance ontology (formal model), there are
>>     two types of information resources (entities) - a class of
>>     entities (TBox or part of ontology schema) and individual
>>     entities (ABox or instances of an entity class).
>>
>>     2. There are two types of attributes - (a) attributes necessary
>>     for an information resource to have to be member of a class of
>>     entities (intensional definition), and (b) set of attributes
>>     associated with a class of entities, but they are not necessary
>>     for an information resource to be member of a class of entities
>>
>>     Given the above points,
>>     > The conceptual model defines an entity in terms of an
>>     identifier and a list of attribute-value pairs.
>>     Does this identify an "instance" entity or "class" entity?
>>
>
>     "instance" indeed
>
>     e.g.:  entity(e0, [ type: "File", location: "/shared/crime.txt",
>     creator: "Alice" ])
>
>
>
>>     >  It is indeed crucial for the asserter to identify the
>>     attributes that have been frozen in a given entity.
>>     Seems to refer to "instance" entity - for those attributes that
>>     form part of the intensional definition of the "class" entity.
>>     For example, a Toyota Corolla Car with vehicle identification
>>     number "1a" will have "frozen" values of "toyota" and "corolla"
>>     for attributes "manufacturing company" and "car model name". But,
>>     it can have "variable" values of "ann" or "tom" for attribute
>>     "current owner".
>>
>     Using the Provenance Abstract Syntax Notation, I could assert two
>     entities (instances)
>
>     entity(e1,[ company: "Toyota", model: "Corolla"])
>
>     entity(e2,[ company: "Toyota", model: "Corolla", owner="tom"])
>
>
>     How do I know the attributes of each entity: company/model for e1
>     and company/model/owner for e2?
>
>     Cheers,
>     Luc
>
>
>
>>     With the above description and examples, can you please clarify
>>     your point again?
>>
>>     Thanks.
>>
>>     Best,
>>     Satya
>>
>>     On Fri, Sep 2, 2011 at 4:52 AM, Provenance Working Group Issue
>>     Tracker <sysbot+tracker@w3.org <mailto:sysbot%2Btracker@w3.org>>
>>     wrote:
>>
>>
>>         PROV-ISSUE-89 (what-entity-attributes): How do we find the
>>         attributes of an entity? [Formal Model]
>>
>>         http://www.w3.org/2011/prov/track/issues/89
>>
>>         Raised by: Luc Moreau
>>         On product: Formal Model
>>
>>         The conceptual model defines an entity in terms of an
>>         identifier and a list of attribute-value pairs. It is indeed
>>         crucial for the asserter to identify the attributes that have
>>         been frozen in a given entity.
>>
>>         Currently, the ontology does not seem to identify these
>>         attributes.
>>
>>         To say that these attributes could be found by looking at all
>>         the properties for this entity does not work with an open
>>         world assumption.
>>
>>         What mechanism do we have to identify these attributes?
>>
>>
>>
>>
>>
>>
>
>     -- 
>     Professor Luc Moreau
>     Electronics and Computer Science   tel:+44 23 8059 4487  <tel:%2B44%2023%208059%204487>
>     University of Southampton          fax:+44 23 8059 2865  <tel:%2B44%2023%208059%202865>
>     Southampton SO17 1BJ               email:l.moreau@ecs.soton.ac.uk  <mailto:l.moreau@ecs.soton.ac.uk>
>     United Kingdomhttp://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 Thursday, 8 September 2011 16:31:44 GMT

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