Re: looking for a social schema

Due to the open world assumption, the value of that counter would 
(probably) we wrong.

If I have
:Peter foaf:knows :Stephen .
:Peter foaf:knows :Marc .

and, based on that knowledge, I added

:Peter myschema:friendnb "2"^^xsd:integer .

this would not be a valid conclusion - there may be a lot more friends 
of Peter which are not in my knowledge base (don't we all have friends 
without a facebook account?), and :Stephen and :Marc might even refer to 
the same person. In other words, with that approach, I would add 
knowledge to my knowledge base which is potentially wrong.

So I would rather refrain from doing that.

Best,
Heiko.

Am 18.11.2011 10:28, schrieb Melvin Carvalho:
> On 18 November 2011 10:20, Heiko Paulheim<paulheim@ke.tu-darmstadt.de>  wrote:
>> Dear Ghalem,
>>
>> since such a property would be in a conflict with the open world assumption
>> underlying the semantic web (you simply cannot tell "how many things of type
>> X are there" in an open world), I suppose there is no serious schema which
>> has such a property.
> What if you kept a separate tally to aggregate total friends as they are added?
>
>> Best,
>> Heiko.
>>
>>
>>
>> Am 17.11.2011 18:40, schrieb Ghalem Ouadjed (EOWEO):
>>
>> Hi everyone,
>> i would like to use a schema which is different and complementary of the
>> foaf one, and which could contain a property like "number of friends".
>>
>> Does someone know an available ontology i could use pls?
>>
>> one of my query would look like :
>>
>> PREFIX rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
>> PREFIX rdfs="http://www.w3.org/2000/01/rdf-schema#"
>> PREFIX dc="http://purl.org/dc/elements/1.1/"
>> PREFIX foaf="http://xmlns.com/foaf/0.1/"
>> PREFIX ............="_"
>>
>> SELECT ?friendnb   WHERE { ?Person   ...;;;;:friendnb   ?friendnb   }
>> ------------
>> | friendnb |
>> ============
>> | "\n330\n" |
>> ------------
>> Thank you in advance for your advices and your time
>>
>> Cheers
>> Ghalem
>>
>> --
>> Dr. Heiko Paulheim
>> Knowledge Engineering Group
>> Technische Universität Darmstadt
>> Phone: +49 6151 16 6634
>> Fax:   +49 6151 16 5482
>> http://www.ke.tu-darmstadt.de/staff/heiko-paulheim

Received on Friday, 18 November 2011 09:34:10 UTC