utype questions

[Douglas Tody]

On Mon, 29 Jun 2009, Matthew Graham wrote:

> So what is wrong with having a static URI that points a SKOS resource that 
> enumerates the different contents - this can be editted as needed and as 
> open-ended as you want but it also have a fixed URI, is (de)referencable and 
> allows for look-ups to see how the same term is referenced in different 
> dialects.

So now we have folks that want a URI which points to an online help
page, and other folks that want a URI which points to a SKOS resource
for this (quite rare) type of data model attribute which could
benefit from use of semantic tools on the value string.  Naturally,
we would change the entire UTYPE mechanism to serve these various
conflicting goals.  What happens the next time we have a different
use case for a different type of attribute?  Perhaps we should do
also away with FITS keywords, UCDs etc. while we are at it?

Lets keep UTYPEs as simple tags used to identify data model attributes
in actual scientific data analysis code, and use other mechanisms
for these more specialized, occasionally useful, but less important
capabilities.  The #1 thing here is to be able to use the data model
for good old fashioned scientific analysis and computation.

 	- Doug


> On Jun 29, 2009, at 2:47 PM, Doug Tody wrote:
>
>> Hi Frederic -
>> 
>> Maybe I am not understanding your question, but semantic inference is
>> a completely different issue from UTYPE.  We are dealing with data
>> models here, not vocabularies.  We do not want to have to infer the
>> field of a data model.  We just need simple static labels, defined
>> within the context of a single (versioned!) model, to allow model
>> attributes to be manipulated in a representation-independent fashion.
>> 
>> Now if our data model contains an attribute (UTYPE) such as Target.Class
>> to specify the class of astronomical object observed, we do need
>> semantic inference to do useful things with the value of this attribute.
>> The UTYPE "Target.Class" is completely defined by the data model,
>> but the contents are an open-ended vocabulary with the problem of
>> multiple dialects and so on.
>>
>> 	- Doug
>> 
>> 
>> On Mon, 29 Jun 2009, Frederic Hessman wrote:
>> 
>>> Sorry to dig back into the utype question, but why isn't the use of 
>>> multiple, translatable vocabularies a la SKOS the ideal (indeed only) 
>>> solution?  Don't want user readability, don't want to enforce a single 
>>> usage, don't need an ontology, don't want to restrict mixing and matching 
>>> as long as I can match what's been mixed, just need a good label.   Or am 
>>> I being naive and/or single-minded?
>>> 
>>> Rick
>>> 
>