Re: LCSH and Linked Data

Owen,

I fear the order of elements may be more complicated in a number of 
cases. The Geographic subdivision ($$z) in particular can wander. This 
depends largely on whether a particular Heading ($$a) or General 
subdivision ($$x) is allowed to be subdivided geographically (some are, 
some aren't). For instance, $$a Education *can* but $$x Finance 
*cannot*, so a book on financing education in England would be under:

650 _0 $$a Education $$z England $$x Finance.

However, the subdivision ($$x) Economic aspects *can* be subdivided 
geographically, so the following would be done instead:

650 _0 $$a Education $$x Economic aspects $$z England.

The general rule is to put the geographic subdivision ($$z) as near the 
end as is legal, otherwise the basic order is 
Topic-Topic-Place-Time-Form. What matters is that the $$z can sometimes 
be before an $$x and sometimes after it. Incidentally these examples and 
much of this wisdom can be found in Chan's "Library of Congress subject 
headings" 4th ed. (p. 120-121) which is very good on this sort of thing 
if you can get hold of a copy.

A couple of other things spring to mind:

- It is possible for other orders in special circumstances, e.g. with 
language dictionaries which can go something like:

650 _0 $$a English language $$v Dictionaries $$x Albanian.

- Some of these are repeatable, so you can have too $$vs following each 
other (e.g. Biography--Dictionaries); two $$zs (very common), as in 
Education--England--London; two $xs (e.g. Biography--History and criticism).

- I'm not I've ever come across a lot of $$bs in 650s. Do you have a lot 
of them in the database?

I'm not sure how possible it would be to come up with a definitive list 
of (reasonable) possible combinations.

Tom

Thomas Meehan
Head of Current Cataloguing
University College London Library Services

Owen Stephens wrote:
> We are working on converting some MARC library records to RDF, and 
> looking at how we handle links to LCSH (id.loc.gov 
> <http://id.loc.gov>) - and I'm looking for feedback on how we are 
> proposing to do this...
>
> I'm not 100% confident about the approach, and to some extent I'm 
> trying to work around the nature of how LCSH interacts with RDF at the 
> moment I guess... but here goes - I would very much appreciate 
> feedback/criticism/being told why what I'm proposing is wrong:
>
> I guess what I want to do is preserve aspects of the faceted nature of 
> LCSH in a useful way, give useful links back to id.loc.gov 
> <http://id.loc.gov> where possible, and give access to a wide range of 
> facets on which the data set could be queried. Because of this I'm 
> proposing not just expressing the whole of the 650 field as a LCSH and 
> checking for it's existence on id.loc.gov <http://id.loc.gov>, but 
> also checking for various combinations of topical term and 
> subdivisions from the 650 field. So for any 650 field I'm proposing we 
> should check on id.loc.gov <http://id.loc.gov> for labels matching:
>
> check(650$$a) --> topical term
> check(650$$b) --> topical term
> check(650$$v) --> Form subdivision
> check(650$$x) --> General subdivision
> check(650$$y) --> Chronological subdivision
> check(650$$z) --> Geographic subdivision
>
> Then using whichever elements exist (all as topical terms):
> Check(650$$a--650$$b)
> Check(650$$a--650$$v)
> Check(650$$a--650$$x)
> Check(650$$a--650$$y)
> Check(650$$a--650$$z)
> Check(650$$a--650$$b--650$$v)
> Check(650$$a--650$$b--650$$x)
> Check(650$$a--650$$b--650$$y)
> Check(650$$a--650$$b--650$$z)
> Check(650$$a--650$$b--650$$x--650$$v)
> Check(650$$a--650$$b--650$$x--650$$y)
> Check(650$$a--650$$b--650$$x--650$$z)
> Check(650$$a--650$$b--650$$x--650$$z--650$$v)
> Check(650$$a--650$$b--650$$x--650$$z--650$$y)
> Check(650$$a--650$$b--650$$x--650$$z--650$$y--650$$v)
>
>
> As an example given:
>
> 650 00 $$aPopular music$$xHistory$$y20th century
>
> We would be checking id.loc.gov <http://id.loc.gov> for
>
> 'Popular music' as a topical term 
> (http://id.loc.gov/authorities/sh85088865)
> 'History' as a general subdivision 
> (http://id.loc.gov/authorities/sh99005024)
> '20th century' as a chronological subdivision ( 
> http://id.loc.gov/authorities/sh2002012476)
> 'Popular music--History and criticism' as a topical term 
> (http://id.loc.gov/authorities/sh2008109787)
> 'Popular music--20th century' as a topical term (not authorised)
> 'Popular music--History and criticism--20th century' as a topical term 
> (not authorised)
>
>
> And expressing all matches in our RDF.
>
> My understanding of LCSH isn't what it might be - but the ordering of 
> terms in the combined string checking is based on what I understand to 
> be the usual order - is this correct, and should we be checking for 
> alternative orderings?
>
> Thanks
>
> Owen
>
>
> -- 
> Owen Stephens
> Owen Stephens Consulting
> Web: http://www.ostephens.com
> Email: owen@ostephens.com <mailto:owen@ostephens.com>

-- 
Thomas Meehan
Head of Current Cataloguing
Library Services
University College London
Gower Street
London
WC1E 6BT

t.meehan@ucl.ac.uk

Received on Thursday, 7 April 2011 12:05:38 UTC