Re: [OEP] New draft of the note on n-ary relations

Dan,

The OEP plans to work on a note dealing with representing time, as soon as 
two new WG members join (Jerry Hobbs and Feng Pan).

When the time note is finished, we plan on another note (listed in the OEP 
description page as "fluents") that will specifically treat the problem of 
representing in the SW "when relations hold", which is what you are asking 
about..  Because the issue is much deeper than just representing n-ary 
relations, we have specifically chosen to leave that out of the n-ary 
note, and address it head-on with dedicated note.

-Chris

public-swbp-wg-request@w3.org wrote on 01/26/2005 04:53:23 PM:

> 
> Good to see this progressing (unlike my various TODOs, embarrasingly).
> 
> I think I have an interesting use-case for you.
> 
> The MusicBrainz project has a lot of metadata about... music.
> 
> Artists, Tracks/CDs, Albums etc. Leigh Dodds has been working on 
> a schema to go on the MB site; currently it serves RDF descriptions 
> of albums etc but there's nothing at the namespace. Recently the MB
> team have come up with something that builds nicely on their core
> dataset, an "Advanced Relationships" system that allows MB contributors
> to catalogue a broader range of relationships amongst the entities
> MB knows about. 
> http://blog.musicbrainz.org/archives/2004/12/advanced_relati.html
> 
> example:
> 
http://test.musicbrainz.org/mm-2.1/artistrel/4d5447d7-c61c-4120-ba1b-d7f471d385b9
> 
> This is imho interesting for n-ary, because the system internally 
> keeps track of more than simple binary relationships. Some relationships 

> are qualified with date ranges. For example, two artists were married 
> between certain dates, or one artists played in another group between 
> certain dates. 
> 
> I've not studied the WD and editors WD as carefully as I should, but 
> from my experience this scenario (wanting to have an idiom for recording
> '"x some-rel y" held between some-dates') is quite a common one. People 
> ask me for similar on the FOAF list periodically, for example.
> 
> Do you have any advice for how MusicBrainz might proceed?
> 
> This btw is likely to be a dynamically growing namespace/dataset, 
> as new relationships are added to the MusicBrainz database. I don't 
> think we need to worry overly about formally capturing the intent 
> w.r.t. temporal qualifications; rather, we just want a nice way 
> of writing that info down, so that applications can get to it 
> again.