Cheat Sheets

Reclassification DDC To LCC


The prime advantage of LCC for a North American library, or a library
purchasing North American material, is that it is more frequently in
CIP and derived MARC records than any other.

There are certainly areas which are problematic, depending of the prime
subject concentration of the collection. We have customers who prefer
to use with LC artistic photography NH, medicine W. Canadian history FC,
Canadian literature PS 800) and/or Canadian KF or Moys. But still the
bulk of material need not be classed inhouse.

The several libraries we've reclassed from DDC to LCC have been
pleased with the slight rearrangement of material, the more
detailed classification, and escaping DCC phoenix (redone) schedules.
LC does not assign new meanings to previously used numbers, although
topics are occasionally shifted.

We have done several DDC to LCC reclassifications. Here are some
practices which we found to work well for patrons, and which eased the
transition for staff.

1) Class all new material in LCC

On day one, class all new material in LCC. Most material will have CIP
with an LCC number. Have classifiers unfamiliar with LCC look the number
up in the schedules to ascertain how it was constructed.

For material which must be originally classified, check the first
subject heading against an LC MARC database (we use ITS MARC English).

LCSH can also be used as an index to the classification, if the
cataloguer does not know which schedule index to consult. The meanings
of at least the first letters should be memorized.

Use the LC Cuttering method as opposed to Cutter-Sanborn. This table can
soon become internalized, and will not have to be consulted.

2) Ribbon shelving

Shift all DDC books down on the shelves, shelving tightly. Shelve the
newly classed LCC books above.

There should be a rough correspondence between subject matter above and
below. There will be less walking for patrons to see both sections for
most subjects. To create this correspondence shelve in this order:

000 100,200 900 300 700

400,800 500 600

There will be some lack of correspondence, e.g., recreation in 790, and
the DDC 000s split between LCC's A and Z. Place labeled wooden blocks
on the DDC shelves to direct patrons to moved classes. It would, w
think, because too much confusion to move parts of classes such as 790s
or 020s to be with their LCC counterparts.

3) Osmotic reclassification

Never reshelve a DDC book in the DDC section. After circulation, return
the book to cataloguing for reclassification. It is also possible to
notify cataloguing of books checked out (by sending the circulation card
or shelf list for libraries having either of those) so that the
reclassification is completed by the time the book is returned.

4) Initially avoid down the shelf reclassification.

With the exception of reference materials (and perhaps reserve materials in
an academic library) avoid down the shelf reclassification for some
time. Down the shelf reclassification would result in time being
absorbed by obscure material lacking MARC records having LCC numbers,
and which may never be used.

5) Weed

When the DDC collection has shrunk to one quarter or less of the total
collection, undertake weeding of the DDC collection. The remainder may
be reclassed leisurely.

6) Use automation

Many have found MarcEdit to be a good tool for inserting LCC numbers
into legacy records.

Please feel free to ask any questions I have not covered or any points
about which I have not been clear.


One of our staff members, Richard Violette, has found the use of
a conversion table such as the following helpful in assigning LCC to
records which have an 082 DDC but no 050 LCC.

Conversion tables : LC-Dewey, Dewey-LC / Mona L. Scott, with the
assistance of Christine E. Alvey. -- Englewood, Colo. : Libraries
Unlimited, 1993.

Personally, I don't favour the use of such tables myself, because the
structures of the two systems are so different. A 5XX number can
suggest Q, as opposed to a 6XX number suggesting T, and of course 8XX
numbers can give you the nationality of the author without having to
look it up. But I prefer to approach LCC by topic.

More helpful I think is a concordance of subject headings and LCC class
numbers. We or the library's systems person should be able to
construct one from the library's records. In the left column you have
the 1st 650 from each MARC record which has an 050. In the right hand
column you have each 050 associated with that first 650. The classifier
would have to check the numbers against the schedule to determine which
is appropriate, but such a concordance does suggest numbers, The same
use can be made of LCSH, but not every heading has a number.

One can have concordances in as many languages as there are
languages of subject headings. If there are OCLC records in the
database, LCC numbers can also be found in 090.

I would like to stress the value of osmotic reclassification in the form
of reclassing materials while on loan, printing the labels, and
remarking upon return from circulation. It is a truism that weeding
should be undertaken before reclassification. This is an expensive,
time consuming process, and needed material could be mistakenly
discarded. If all circulated materials are reclassed while on loan for,
say, two years, there will be a much smaller body of material to be
examined for possible discard.

Standard material which circulates is more likely to have a record with
an 050 LCC class number. Classifiers could become familiar with the
classification before having to assign so many class numbers originally.

You might want to do down-the-shelf reclassification of the reference
collection, and of the reserve collection during the holiday before
school reopens. But for the bulk of the collection, I suggest delaying
down the shelf reclassification for from two to five years. Undertaking
that at the outset can bog you down with esoteric little used material.

If a branch of any system uses an alternate classification, e.g.,
Moys law classification, the collection should use the same
classification for law. The Moys' "K" intershelves with LCC, replacing
LCC's K. The difference between LCC's K for law and Moys' K for law, is
that LCC's arranges law by jurisdiction, and Moys' arranges common law
jurisdictions together by topic.

In Canada there is an adaptation of LCC's KF (U.S. law in LCC) which also
arranges all common law jurisdictions together by topic. This means
that in libraries using that adaptation, no use is made of LCC's KD
British law and KE Canadian law, If you see such a KF number in 055,
it should *not* be used unless the library uses that adaptation.

If a university has a medical school, it might want to consider NLM
(National Library of Medicine) classification. It uses "W" for
medicine, replacing LCC's R, and like Moys, intershelving with LCC.
As with Moys, if the branch library uses NLM, medical books in the main
collection should also be in NLM.

This would effect the reclassification of DDC 340 and/or 610.

SLC assigns class numbers for book jobbers on the basis of ftp files,
and could do the same for any library reclassing to LCC.