- From: David Booth <david@dbooth.org>
- Date: Mon, 17 May 2010 21:33:56 -0400
- To: Peter Ansell <ansell.peter@gmail.com>
- Cc: Jakub Kotowski <jakubkotowski@gmx.net>, Jitao Yang <jitao.yang@gmail.com>, semantic-web@w3.org, www-rdf-interest@w3.org
On Tue, 2010-05-18 at 09:04 +1000, Peter Ansell wrote: > On 18 May 2010 06:58, David Booth <david@dbooth.org> wrote: > > Right, but it is unfortunate that we do not have an established > > *standard* way to represent higher-arity relations. Instead we have > > *multiple* ways to do it, and different people do it different ways, > > which means that software cannot automatically recognize them as > > higher-arity relations. > > > > For example, if we had a standard "marker" property like this: > > > > :higherArityRelation a rdfs:Property ; > > rdf:comment """A higher-arity relation (i.e., not restricted > > to binary relations) between the subject and the > > items in the object list. The object must be a > > list; each element of the list participates as > > one of the participants in the relation. Thus, > > a tertiary relation uses a list of two items.""" . > > > > then for the diagnosis use case in > > http://www.w3.org/TR/swbp-n-aryRelations/#useCase1 > > we could write something like the following: > > > > foo:has_diagnosis a :higherArityRelation . > > > > foo:christine foo:has_diagnosis ( foo:Breast_Tumor foo:HIGH ) . Sorry, I meant to write: foo:has_diagnosis rdfs:subPropertyOf :higherArityRelation . foo:christine foo:has_diagnosis ( foo:Breast_Tumor foo:HIGH ) . > > > > and software could recognize this as a tertiary relation, perhaps > > optimizing or rendering it differently. > > The main question then is what optimisations are going to be > performed, and what level of difference in human visual rendering is > needed? If the application is designed specifically for the scenario > then it won't need to know that the relation is higherArity because > that knowledge will have been programmed into the system as part of > arranging for the application to interpret different parts of the list > as it requires. > > The only optimisations or rendering differences would then be with > generic browsing software from what I can tell. It would need to be > different to a non-higherArity list display or treatment, whatever > that is currently. Right, that's what I meant: generic software could recognize them. For example, the Cyc engine already has ways to deal with higher-arity relations in its native code, but it doesn't have any way to know that certain patterns it sees in RDF are really meant to represent higher-arity relations. -- David Booth, Ph.D. Cleveland Clinic (contractor) Opinions expressed herein are those of the author and do not necessarily reflect those of Cleveland Clinic.
Received on Tuesday, 18 May 2010 01:41:13 UTC