Multiple definitions

[Rob Seaman]

I think the discussion may benefit from explaining Rick's punchline.   
Google "Abell 1656" and from the first item on the list we learn:

	"Abell 1656 is a massive aggregation of galaxies 400 million light  
years distant."

...that is, not a comet at all.

The second Google item tells us that Abell 1656 is also known as the  
Coma Cluster.  A few items further down, we learn that it is called  
that because it resides in the constellation Coma Berenices.

The non-astronomers here perhaps will appreciate the explanation of  
the confusion of terms, although I think only an astronomer would find  
Rick's joke funny :-)  And at that, perhaps only someone previously  
familiar with the Coma Cluster (http://adsabs.harvard.edu/abs/1984BAAS...16..989S 
).

Ed's suggestion for using altLabels seems very helpful to me.  There  
is a level of context that will always be needed to interpret  
astronomical usage and one could imagine bouncing around the altLabels  
for a number of terms in some document (for instance, in a detailed  
definition of some other term) to narrow in on the proper context.  I  
presume this is how Google ranks its hits.  (And in case it wasn't  
clear, I learned all this from the Google headings, without clicking  
through to any source material.)

So yes - I support adding copious altLabels if SKOS permits this.  Is  
this the anticipated usage for these fields?

Of course, there will come the inevitable discovery of a comet in Coma  
Berenices, and that comet's coma may well be imaged by telescopes with  
non-negligible optical coma.

Rob
--

Ed Shaya wrote:

> Well, I suppose I should say something about why I think 1 term-1  
> definition is best.  If you claim some term is narrower than  some  
> other term,  then it better be clear which of the definitions of the  
> first term is narrower than which of the definitions of the second  
> term.  Otherwise, I am searching for info on comets and suddently I  
> am getting suggestions from the system that I should follow the path  
> on optical distortions.  At which point I close that window.
>
> Ed Shaya wrote:
>>
>
>> Wouldn't it work this way if we allow altLabels+prefLabels to be  
>> non-unique?  So for this case,
>> comet_coma would have id="comet_coma", prefLable="coma of comet"  
>> and altLabel="coma".
>> But the distortion coma would have id="coma", prefLabel="coma  
>> distortion",  altLabel="coma".
>> The point is to have unique terms for unique definitions.
>> This is probably what you meant.  Yes?
>>
>> Frederic V. Hessman wrote:
>>
>>> Multiple definitions may be cumbersome, but they are reality.   I  
>>> would rather have too many than too few to choose from.   Here's  
>>> my best attempt at a "scenario" to show that computers should like  
>>> multiple definitions:
>>>
>>> VO-app:  "What would you like to observe today?"
>>> Astronomer: "The comet from yesterday's APOD."
>>> (pause to look for an IVOA vocabulary which explains what "APOD"  
>>> means)
>>> VO-app: "OK"
>>> (pause to find an HTN telescope)
>>> VO-app: "The camera's FOV is only 10 arcminutes: what part of the  
>>> object would you like to observe first?"
>>> Astronomer: "Nucleus."
>>> VO-app: "Completed, downloaded and displayed in your VO-viewer.    
>>> Next target?"
>>> Astronomer: "Tail."
>>> VO-app: "Completed, downloaded and displayed in your VO-viewer.    
>>> Next target?"
>>> Astronomer: "Coma."
>>> VO-app: "Slewing to Abell 1656..."