On Fri, Mar 27, 2015 at 12:46 PM, Kelley McGrath <[log in to unmask]>

> I strongly disagree with the statement that  someone who understands
> MARCXML can do whatever they want with the data. I think I have a pretty
> good grasp of MARC and I have spent countless frustrating hours trying to
> get information out of MARC records (and not always succeeding).
> Granted, I'm not a developer, but I've worked with people who are good
> developers so I don't think that's the bottleneck.

I'll stick to LCSH and related topics in this note, since that is the area
I have studied the most, and thus one about which I know the least

* Sometimes the data isn't in the MARC XML record.

For example:

   - LC subjects files do not record NT relationships.  This information
   may be inferred.
   - Sub-divided headings do not necessarily carry BT relationships to the
   implied broader terms (which may not established).
   - Headings, Inverted is not related to Headings.

* Sometimes extracting information from the data  requires deep
common-sense reasoning to extract relationships/patterns. e.g.

   - Headings are established as compound noun phrases.  Ask a linguist
   about the semantics of English compound noun phrases...

* Sometimes processing requires knowledge from the SCM *as it existed at
the time a heading was created/applied

I will ignore the problematic  fact that the structure of LCSH has been
seriously corrupted for getting on 30 years (since the conversion to

[I will also ignore the fact that as of 2011 there was no peer-reviewed
literature that demonstrated that subdivided subject headings could be said
to have meaning.  Granted, at that time there had only ever been one study,
and that with problematic methodology.]

BibFrame solves all of this  by  +++ATH