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Re: Time for quintuples?

From: Bob Ferris <zazi@elbklang.net>
Date: Sat, 25 Sep 2010 15:08:33 +0200
Message-ID: <4C9DF451.5050807@elbklang.net>
To: semantic-web@w3.org
Hi everybody,

I tried to model the knowledge representation with help of quintuples 
(quads + named graphs). I introduced therefore also a statement ID 
similar to the proposal from [4]. However, I don't want to use this only 
internally. That's why the statement ID should also be an URI.
Please have a look at the result [5] ;)

I applied the reification statement approach as description for the 
cognitive characteristic and for the related weight. Furthermore, I 
sketched some provenance information, i.e. for the scale description, 
named graph description and default graph description.

What do you think about this modelling?

I probably noticed a disadvantage of the Triplesets approach: the 
provenance information, e.g. an update date, is modelled with help of a 
concept, which may cause some overhead, because especially an update 
date can be simply modelled by one triple/quad, or?

more notes inline

Am 24.09.2010 15:34, schrieb Bob Ferris:
> Hi everybody,
>
> Am 24.09.2010 14:11, schrieb Nathan:
>> Toby Inkster wrote:
>>> On Fri, 24 Sep 2010 01:12:45 +0200
>>> Bob Ferris <zazi@elbklang.net> wrote:
>>>
>>>> However, if I have for example three "shortcut relations" (e.g. a
>>>> skill, an expertise and and interest) in a graph, which have all the
>>>> same topic, I can't match them to the related cognitive
>>>> characteristic statement (as you can also see in the original
>>>> example[1]).
>>>
>>> What's wrong with this?
>>>
>>> ex:APerson
>>> cco:skill <http://dbpedia.org/resource/Football_(soccer)> .
>>>
>>> ex:CC1
>>> a cco:CognitiveCharacteristic ;
>>> cco:agent ex:APerson ; #added this
>>> cco:characteristic cco:skill ; #added this
>>> cco:topic <http://dbpedia.org/resource/Football_(soccer)>;
>>> wo:weight [
>>> a wo:Weight ;
>>> wo:weight_value 6.0 ;
>>> wo:scale ex:AScale
>>> ];
>>> cco:activity
>>> <http://sw.opencyc.org/concept/Mx4rwJRiEpwpEbGdrcN5Y29ycA> .
>>>
>>> The following N3 rule would allow you to infer the shortcut property
>>> from the longer form:
>>>
>>> {
>>> ?cc
>>> cco:agent ?s ;
>>> cco:characteristic ?p ;
>>> cco:topic ?o .
>>> }
>>> => { ?s ?p ?o . } .
>>
>> nice, +1 for Toby's approach from me, and likewise using n3 for all
>> you're named graph needs.
>
> Yes, I proposed this idea before also on the FOAF dev mailing list (see
> [1]):
>
> "- introduce a further property with a domain of
> cco:CognitiveCharacteristic, which directs to the applied cognitive
> characteristic, e.g. ex:CC1 cco:applied_cognitive_characteristic cco:skill
> -> then we might somehow fall back to the "standard"
> reification approach (subject relation -> cco:agent/cco:habit;
> predicate relation -> cco:applied_cognitive_characteristic;
> object relation -> cco:topic)"
>
> However, it might have the mentioned drawbacks ;)
>
> With the quad based approach, one would "bind" the reification statement
> directly to its "shortcut relation".
> Furthermore, what would happen, if you like to describe a cognitive
> pattern of the same category, e.g. a skill, and with the same topic,
> e.g. soccer, which should be related with two activities, e.g. goal
> scoring and goal keeping* (which should have different weightings etc.).
> Then you will need two cognitive characteristics descriptions, which are
> "bound" to their related "shortcut relations", or?

I would agree with your approach, Toby, to apply a rule for the mapping 
between "shortcut relations" and their descriptions. Although they are 
not in an one-to-one relation, the modelling might fit its purpose:

- I can get all related cognitive characteristic descriptions of a 
cognitive characteristic "shortcut relation" (one-to-many)
- I can summarize cognitive characteristic descriptions of a specific 
cognitive pattern and with the same topic to one "shortcut relation" 
(many-to-one)

So I think applying a rule here might be enough ;)

>
> I'm getting more and more the opinion that we need a separation between:
> - 'internal context', which should represent "semantically related
> information" to the triple (here identified as reification statement)
> - 'external context', which represent "semantically unrelated
> information" to the triple (here identified by the Named Graph
> entailment and the description of the Named Graph)
> as it was a result of Tolle's research (see "Understanding Data by their
> Context Using RDF"[2] for example, or [3], because the design of
> Triplesets was also inspired by this "separation").
>
> Furthermore, the same idea was probably similar applied by the approach
> of the metaK framework (see "Querying for Provenance, Trust, Uncertainty
> and other Meta Knowledge in RDF"[4]), where they called the 'external
> context' 'meta knowledge' and introduce a separation between knowledge
> and meta knowledge (with separate interpretation of meta knowledge
> properties etc.). I really like the proposal, which is described in [4],
> because they are delivering a good explanation of their intended
> semantics and how they would integrated their approach in the existing
> Semantic Web framework.
> Although, this proposal might have some drawbacks in scaling to a Linked
> Data scenario, because one have to define the intended meta knowledge
> properties (that mark them somehow) and their corresponding
> interpretation functions for query processing (this is currently done
> via their Java framework). Maybe a Semantic Graph based description
> might be good, so that other information consumer can also use this
> knowledge for query processing.
> However, what would happen, if one have to mix different meta knowledge
> property definitions via a semantic federation framework, e.g. in one
> source a property is assigned as meta knowledge property and in another
> one not, or the interpretation functions of a meta knowledge property
> are different.
> Furthermore, can't there also be a fall-back into a ranked result
> recommendation, if the filtering and/or ranking conditions of a query
> wouldn't be fully fulfilled and the exact search result would hence be
> empty? For instance, they drew an example that a more recent source
> would outperform an older, but what will happen if the newer one has a
> lower certainty?
>
> Cheers,
>
>
> Bob
>
>
> *it might not be the best example, but hopefully good enough for
> explanation ;)
>
>
> [1]
> http://lists.foaf-project.org/pipermail/foaf-dev/2010-September/010422.html
> [2]
> http://www.dbis.informatik.uni-frankfurt.de/~tolle/Publications/2004/AISTA04.pdf
>
> [3] http://www.ontotext.com/ordi/ORDI_SG/ORDI_SG_Specification.pdf
> [4]
> http://www.uni-koblenz.de/~staab/Research/Publications/2009/jws-meta-knowledge.pdf

Cheers,


Bob


[5] http://smiy.sourceforge.net/cco/examples/N3/cco_-_football_example.qng
Received on Saturday, 25 September 2010 13:09:38 GMT

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