Re: VOConcepts

From: Andrea Preite Martinez <andrea.preitemartinez-at-rm.iasf.cnr.it>
Date: Tue, 14 Jun 2005 15:06:39 +0200


Dear Rick,

I think I will not vote.

I find the discussion (any discussion) among people with different ideas very stimulating.
And sometimes also more useful than perfect agreement. Reducing the size of the group until you can feel eventually "among us" is not good at all in real life, certainly not in the VO.

Just to show you that you are not the only one "uneasy" with somebody else's point of view, I'll make an example of how "uneasy" could feel an UCD-folk like me.
Take for instance the UCD you proposed few days ago:

instr.obsty.site;weather.seeing just to express "seeing"

When I saw it I made a jump on my chair: why? In inverse order of importance:

  1. The UCD-like syntax is wrong: first the "quantity", then the "qualifier" it should read: weather.seeing;instr.obsty.site
  2. We are proposing UCD-words, not UCDs. If you propose an independent word for "seeing", ok, it's :weather.seeing
  3. My mind works in terms of "how to assign ucd-words starting from a description, and then build an UCD" e.g. in term of the process to build an UCD from one or more keyword(s): the "keywords => ucd-words => UCDs" chain. It is impossible (in this framework) to go from the single keyword
    "seeing" to an UCD composed of two UCD-words
    (each one of these UCD-words needs its own description).

Let's reverse the roles: you jump on the chair when you see the description of the src.class.* words.
You are perfectly right. What is not said is that I do not use the description
field to assign words/ucds: I use a series of words (keywords derived from the description) that are OR-ed, which is exactly equivalent to the loosier description you suggest.

As I already said, the ucd vocabulary is not only composed of words that are "quantities". More and more "objects" are creeping in, and I can imagine the development of two sub-lists :

a "q-list" slowly evolving (or even stabilized; after all the number of new (astro-)physical quantities per year is probably very easy to control!!)

and an "o-list" (or whatever name we decide for it!!) for "non-quantities",

both lists with the same syntax (just for simplicity and
"interoperability" (!!),

so that we can continue to build UCDs of the form:

word[q-list];word[o-list] ...

as we do today without knowing that we are actually doing it (!)

Andrea


Andrea Preite Martinez                  andrea-at-rm.iasf.cnr.it
Istituto di Astrofisica Spaziale        Tel.:+39.06.4993.4641
Area di Ricerca di Tor Vergata          Fax.:+39.06.2066.0188
Via del Fosso del Cavaliere 100         Cell:+39.339.3817355
00133 Roma
Received on 2005-06-14Z15:06:59