I was looking for this last month (there may even be a thread in the
archives from me on it); I didn't anything very suitalbe.
The only potentially useful thing I found, is that id.loc.gov does
include mappings for _some but not all_ LCSH authority records. I think
these mappings were included in the original LCSH authority records,
they are not value added by id.loc.gov. So any source of LCSH authority
records would also have this info.
For example, look under "LC Classification" at
I think some LCSH authority records may have more than one suggested LCC
too (which is reasonable and makes sense).
You can look up records id.loc.gov by known term by doing, say:
A pre-coordinated LCSH string in a MARC record may not exactly
correspond to an authority record, so you may have trouble matching
there, have to figure out which part of the LCSH string matches the auth
record. And then, not every LCSH auth record has suggested
corresponding LCSH, only some of them do.
But that's pretty much the only thing i was able to find when I looked
In theory, I think a prommissing approach would be to take an existing
corpus of bib records, and assemble statistical correlations between
LCSH and LCC. For instance, of all the records with a certain LCSH
assigned, maybe there are 12 LCC's represented, and some more than
others. This would give you some pretty likely candidates for
appropriate LCC's for a given LCSH. It would take some algorithmic
tweaking probably. It would work best on a huge corpus like OCLC or LC
(and I think I recall a non-free product that does exactly this), but
could possibly bear fruit on a reasonably large corpus like an
individual research library too. It would be an interesting project for
someone to undertake, if it resulted in open data on LCSH->LCC
correspondences, it would be useful to many.
On 12/10/13 8:18 AM, Irina Arndt wrote:
> Hi CODE4LIB,
> we would like to add DDC classes to a bunch of MARC records, which contains only LoC Subject Headings.
> Does anybody know, if a mapping between LCSH and DDC is anywhere existent (and available)?
> I understood, that WebDewey http://www.oclc.org/dewey/versions/webdewey.en.html might provide such a service, but
> · we are no OCLC customers or subscribers to WebDewey
> · even if we were, I'm not sure, if the service matches our needs
> I'm thinking of a tool, where I can upload my list of subject headings and get back a list, where the matching Dewey classes have been added (but a 'simple' csv file with LCSH terms and DDC classes would be helpful as well- I am fully aware, that neither LCSH nor DDC are simple at all...) . Naïve idea...?
> Thanks for any clues,
> Irina Arndt
> Max Planck Digital Library (MPDL)
> Library System Coordinator
> Amalienstr. 33
> D-80799 Muenchen, Germany
> Tel. +49 89 38602-254
> Fax +49 89 38602-290
> Email: [log in to unmask]<mailto:[log in to unmask]>