Vocabularies and VOEvent

[Roy Williams]

The vocabulary effort is very exciting, there are a lot of messages. But 
I am still waiting for the cost benefit analysis. The number of emails 
sent to this group shows us the cost. But, for myself at least, I am 
torn between the two approaches to defining "Why" this event may have 
occurred, asking if the benefits of the higher cost version outweighs 
its costs.  The older I get, the more I want to keep with KISS (Keep It 
Simple and Sufficient), and the less I am interested in finding the 
general solution. Anyway, here are the choices for VOEvent 2.0 as I see 
them:

(1) The KISS approach:
We could follow the astronomer's telegram (*) and define a short list of 
words to be used to describe event hypothesis, such as those below, with 
"check all those that apply". The query and API is simple:
    select * where event.why == "Novae" .....
     if eventType == "Novae" then .....
If this is not sufficiently precise, I would like to know the plausible, 
real-life situation, where such imprecision will become a burden. In

(2) The vocabulary approach:
I know very little about it except that precision of expression is 
possible (eg "I want Supernovae Ia but not Ic"). I would like to be 
disembarrassed of my horrible prejudices. I worry that there are many 
vocabularies with no agreement. I worry that there are many 
representation technologies for vocabularies that use complicated 
languages. I worry that use of vocabularies will require knowledge of 
complex matters like namespaces, schema extension, sparql, skos, rdf, 
owl, etc etc. I worry about no being able to use SQL or even Xquery but 
must learn a new query language. I worry that the creator of the VOEvent 
will also need to understand these complex technologies, meaning that 
few event streams will be done this way. Are any of these valid worries?

I do not want to pooh-pooh this promising vocabulary effort. It's just 
that  I have not seen the reasons why (2) is so much better than (1) 
that the effort is justified.

Roy



(*) http://www.astronomerstelegram.org/
click on "Post a New Telegram", you see these categories:
Request for Observations, A Comment, AGN, Asteroids, Binaries, Black 
Holes, Comets, Cosmic Rays, Cataclysmic Variables, Globular Clusters, 
Gamma-Ray Bursts, Meteors, Microlensing Events, Neutron Stars, Novae, 
Planets, Planets (minor), Pulsars, Quasars, Soft Gamma-ray Repeaters, 
Solar System Objects, The Sun, Supernovae, Supernova Remnants, 
Transients, Variables, Stars