Multiple definitions

[Alasdair J G Gray]

Rob Seaman wrote:
> 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).
Thank you for the very helpful explanation. I'm afraid that I had given 
up on this line because of not understanding the example.

> 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. 
I agree with Ed that each term/concept in a vocabulary should contain 
just one preferred label and more importantly one definition. The whole 
point of this work is to be able to distinguish between the multiple 
meanings of terms.
>
> 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?
Absolutely. There are no limits on the number of alternative labels. Of 
course, the applications that make use of the vocabularies will have to 
be wary that the same label can be used for different concepts and get 
the user to clarify which of the meanings they intended. This is why it 
is so important to have definitions for the terms as the application 
would only be able to display the labels back to the user if the 
definitions did not exist.

Alasdair
>
>
> 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:
>>>
>>
>>> 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..."

-- 
Dr Alasdair J G Gray
http://www.dcs.gla.ac.uk/~agray/

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