A couple years ago, I used a crossmap of LC call numbers to subject
headings (admittedly out of date) to provide subject-labeled sort by call
number on an experimental catalog
The mapping came from  Mona Scott. Conversion

I don't know how robust this is, but try searching a word that will appear
across subject areas, like "brown", to see the classification/subject

I read the tables into a database, and in a batch process, coded each call
number division by how deep into the hierarchy it was linked - the number
of indents from 1 to 6.  My ambition was to then try to find the most
frequently used subject headings in each step of the hierarchy (limited to
a workable range) to try to generate some semantic-net-like set of links
between subject headings and classification.  But I never was able to
pursue that goal.

Cindy Harper, Systems Librarian
Colgate University Libraries
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On Sun, Oct 30, 2011 at 5:58 PM, David Friggens <[log in to unmask]>wrote:

> > Clicking on one of Ben Shneiderman's treemapping projects reminded me
> that
> > I've always thought treemaps [1] would serve well as a browsing interface
> > for library and archive collections because they work well with
> hierarchical
> > data.
> I played around with this earlier in the year, wanting to provide a
> drill-down into our collections by call number.
> For our Education Library's Teaching Collection, I used a three-level
> visualisation of items based on Dewey hierarchy, and coloured by the
> proportion of "new" (post 2006) items. I never put it online anywhere,
> so have attached it here.
> Dewey was pretty easy to get labels for the first three levels, and
> that seemed reasonable enough for most areas. But the majority of our
> items are LCC, and that's where I ran aground. The labels for the
> first two letters are readily available, but far too general to make
> this interesting. I couldn't seem to find any useful data in machine
> readable format. Sourcing another level down from LoC [1] or Wikipedia
> [2] seems tantalisingly close, but there's a whole lot of manual
> effort in turning these (incomplete) ranges into something usable.
> Cheers
> David
> [1]
> [2]
> --
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