Datalink Feedback VI: Semantics

[Norman Gray]

Mark, Markus and all, hello.

On 2014 Apr 25, at 10:03, Mark Taylor <m.b.taylor at bristol.ac.uk> wrote:

> On Fri, 25 Apr 2014, Markus Demleitner wrote:
> 
>>> Q. Where do we specify the process for updating the vocabulary
>>> itself? Is that something Semantics WG would have a general policy
>>> about?
>> 
>> Ah well.  The precedent we have is the UCD addition process, for
>> which there's a standard of its own, and given that AFAIK nobody has
>> even tried it I suspect that's not a particularly good precedent.
> 
> I'll note another relevant precedent. 
> 
> For SAMP the semantic content comes in the form of MTypes,
> which are effectively RPC definitions (procedure name, arguments,
> return values, and semantic intent).  The "core" MTypes
> (mostly associated with hub and client lifecycle) are defined
> in the SAMP standard.  All the others (the ones that make SAMP
> useful, things like exchaning tables, images, sky positions)
> are simply listed on a wiki page
> (http://wiki.ivoa.net/twiki/bin/view/IVOA/SampMTypes).
> There is no formally defined process for updating this list,
> but informally people make suggestions on the mailing list,
> and if nobody has objections, they just edit the page.

Indeed.  The UCD precedent was one that occurred to me, and which I also wanted to shy away from, since it's turned out to be probably unusably heavyweight in practice.  The process has been invoked in the past, and there have been UCD updates, but it can't be called agile.

I think the SAML MTypes model is much more appropriate for the development of a Datalink term list.  Markus, you proposed a process which involves the TCG: that element of oversight has attractions, but there's still a danger of over-formalising that.

How about language like: "The DAL WG will from time to time reissue the Datalink core term list, in consultation with the community.  No terms will be removed from the list."

All the best,

Norman


-- 
Norman Gray  :  http://nxg.me.uk
SUPA School of Physics and Astronomy, University of Glasgow, UK