Fwd: VOConcepts

[Rob Seaman]

Begin forwarded message:

> From: Roy Williams <roy at cacr.caltech.edu>
> Date: June 14, 2005 8:47:54 AM MST
> To: ucd-sci at ivoa.net
> Cc: Roy Williams <roy at cacr.caltech.edu>
> Subject: Re: VOConcepts
> Reply-To: ucd-sci at ivoa.net
>
>
>
> On Jun 14, 2005, at 12:47 AM, Frederic V. "Rick" Hessman wrote:
>
>
>>  I think we'd all appreciate a general comment on whether ucd-sci  
>> is the right place for a discussion
>> of what we have tenatively called VOConcept.
>>
>
> Rick
>
> It says in the UCD document "UCD describe astronomical quantities",  
> meaning that they are "semantic meaning of data quantities", for  
> example "phys.temperature".  The implication is that UCD is NOT  
> something like "satellite.Phobos;planet.Mars" and it is NOT  
> something like "image.jpeg;human.JacquesChirac". I believe that the  
> scope here is correct, and that extensions in to these other areas  
> of knowledge will slow down the well-developed and sophisticated  
> UCD effort.  One of the best things about UCD is that it has been  
> mined from thousands of table instances written by hundreds of  
> astronomers, and therefore has unimpeachable credentials as a  
> representation of the astronomical community.
>
> However, we should tackle wider questions when supported by use  
> cases from the community. I believe the UCD effort should become  
> part of a wider "semantics" effort, which may use UCD syntax for  
> other areas of knowledge (eg. astrophysical events), or it may use  
> OWL or RDF or other syntax. Frankly I don't care about the syntax  
> part, that comes later: what is important in these semantics  
> efforts is formalizing some branch of knowledge so that computers  
> can record, compare, and deduce.
>
>
>> Yes, there are lots of potential relations between VOConcept and UCD
>>
>
> I would prefer not to use the term "VOConcept", as it is too vague.  
> I think the Semantics WG should concentrate on small, well-defined,  
> areas.
>
>
>> You might ask us to please shut up and worry about this later, but  
>> we're in the final throes of finishing VOEvent 1.0 and need to  
>> make a short-term decision about whether we ignore the problem of  
>> naming for now (at the cost of a loss of naming capability) or  
>> make an initial plunge in the direction of a UCD-like VOConcept  
>> (whatever you want to call it).
>>
>
> I think that VOEvent should be published as version 1.0 Working  
> Draft without any formal semantics for describing events, but  
> rather describe events in natural language: "Looks like an  
> exploding square galaxy" would be a typical description. Then in  
> VOEvent 1.1 we can tackle formal semantics and other matters.
>
> And that formal description of astronomical events should not be  
> called "VOConcept", but something more specific, such as "Unified  
> Event Description", or "VOEventDescription". The first task of that  
> discussion group is define what is the area of knowledge that is  
> being covered, and agree to a short paragraph expressing what is an  
> is not being formalized into syntax. For example, in  
> VOEventDescription, is it an event when Michael Jackson is  
> acquitted? How about when a new planet is discovered? How about a  
> flare from a star that flares every 2 weeks?
>
> I believe that defining scope is the key to progress here, and that  
> the tighter that scope, the better chances for agreement. Otherwise  
> we are caught in a morass of ontological questions. In the words of  
> Bill Clinton, "It depends upon what the meaning of the word is  
> means. "
>
>
>> Please vote:
>> ___ Please stop talking about VOConcept in this list - we have  
>> enough to worry about as it is.
>> ___ I think the two issues are still related enough to warrant  
>> inclusion in the ucd-sci discussion list for now.
>>
>> Based upon the tally, we can decide to continue (at least now and  
>> then) or to start a new list.
>>
>
> I think the discussion of VOEventDescription should take place in  
> the VOEvent mailing list, perhaps copying the entire Semantics WG  
> when wider issues come up.
>
> Roy
>
>