> By attaching the same UCD to values from two different tables we are
> asserting that ..... these values represent identical "things".
We are asserting that there exists a context in which they are the same. Question: In what context is an R-magnitude and a B-magnitude the same thing? Answer: when you count photons without regard to their wavelength.
> some purely mechanical process be sought to convert the column
> headings from each month's new batch of tables from the literature
> into UCDs.
That was the original conception. The only structure was some grouping. Then we tried to get clever, and replaced the single UCD "magnitude error" by two components ("magnitude" and "error"). That was the slippery slope towards a data model. And here we are up to our asses in ontological alligators!
> ..... building a simple kind of data model of astronomy.
> ..... evanescent dream of a full astronomical ontology
I don't think these things are possible. Everyone has their own opinion. It would be too complex and unwieldy.
> The way to extend a robust UCD process into the future is to provide
> an explicit namespace mechanism from the start.
We tried this before about 2 years ago, but it was vetoed. The problem with namespace is that it reduces interoperability -- there was a fear that everyone would simply use their own namespace.
Roy Received on 2005-06-29Z18:28:21