Corey A Harper
Mon, 16 Feb 2009 07:26:33 -0800
Hi Alistair,I think I may have mentioned this to you before, but if not, have you seen the early MIT / SIMILE work on MODS->RDF? [1] While I think there's a few inaccuracies therein, and it certainly doesn't help at all with the RDA/FRBR bits of your analysis, it might still be worth looking at, even if only to inform or augment the work you've got going.
I'm really excited to see some of this in action as you continue to make progress.
Thanks, -Corey [1] http://simile.mit.edu/wiki/MARC/MODS_RDFizer Alistair Miles wrote:
Hi Karen, On Fri, Feb 13, 2009 at 06:46:37AM -0800, Karen Coyle wrote:Alistair,I did start an analysis of RDA and MARC, but didn't get very far. I'll take that up again. What I was mainly finding is that there are a lot of RDA elements that are listed for more than one MARC element, e.g.$a Personal name* = 9.2.2 Preferred Name for the Person* $b Numeration = *9.2.2 Preferred Name for the PersonYes, I expect there will be lots of issues like this, in both directions. Please do continue your analysis, this type if insight is very useful. I should say that I don't hope to create either a complete or perfect mapping from mods to RDF/RDA/FRBR. Rather I hope to map just enough to capture a significant amount of useful information, to demonstrate the potential for further work in this direction. Cheers, AlistairThere are ones that go the other way, as well, where RDA is more specific than MARC. It made me wonder how it is that we use the specific MARC elements: are they needed for display? do they help input? are they arbitrary?I haven't looked at MODS, however, and there isn't a mapping provided between MODS and RDA. I'll think about that, however.kc *Alistair Miles wrote:Hi all, This is just an update to say that I've converted the LOC/scriblio data to marc xml and from there to mods xml. My next step is to do some analysis of the loc data in mods xml to get an overview of the elements used, then to try to design at least a partial mapping from mods xml to RDF using the RDA and FRBR schemas. FYI the marc xml and mods xml versions of the LOC/scriblio data can be downloaded from the links below... http://dcmi-rda.s3.amazonaws.com/locdata/part01-marcxml.tar.gz http://dcmi-rda.s3.amazonaws.com/locdata/part01-modsxml.tar.gz http://dcmi-rda.s3.amazonaws.com/locdata/part02-marcxml.tar.gz http://dcmi-rda.s3.amazonaws.com/locdata/part02-modsxml.tar.gz [...] http://dcmi-rda.s3.amazonaws.com/locdata/part29-marcxml.tar.gz http://dcmi-rda.s3.amazonaws.com/locdata/part29-modsxml.tar.gz Each download is a gzipped tar containing a *set* of up to 25 xml files. Each of these files is a 10,000 record split of the data in the corresponding part. I broke each part into 10,000 record splits so I could process the transformations more easily. N.B. there is a bug in part 13 split 25, for some reason the marc xml output was incomplete so up to 10,000 records could be missing. FWIW I initially tried the conversions without splitting each part. I.e. I converted each original marc file into a single marc xml file, then tried to transform that to a mods xml file via xsltproc. However I found you need more than 7GB ram to do the marcxml to modsxml transform on a whole part (I tried it on a large ec2 instance), so that's when I decided to split each part into smaller chunks, which I figured would be faster to process and more amenable to parallel processing (transforming all the splits from marcxml to modsxml took a couple of hours on a c1.xlarge ec2 instance, running up to 10 transformations in parallel; it can also be done on a laptop, but takes ~10 times longer). Btw if anyone else has experience of the marcxml->modsxml transform on a file of similar size do let me know, I don't do a lot of xslt-ing so may be missing some tricks for making it work on smaller computers. Cheers, Alistair On Mon, Dec 22, 2008 at 03:31:50PM -0500, Ed Summers wrote:Hey Alistair: On Mon, Dec 22, 2008 at 1:16 PM, Alistair Miles <alistair.mi...@zoo.ox.ac.uk> wrote:Any tips for how I could turn these data into RDF?If you want to work specifically with that dataset you could download the different parts Karen pointed you to, and convert to MARCXML using an efficient tool like yaz-marcdump [2]. yaz-marcdump is nice it will convert from MARC-8 to UTF-8. Once you've got it in MARCXML you could then use a stylesheet like LC's [2] to convert to DublinCore flavored RDF. This might be kinda lossy for your RDA work though, so you might want MARCXML->MODS [3], and then use the MODS->RDF conversion that the Simile folks created (which Karen also pointed you to) [4]. In fact Simile used that stylesheet on their own MIT Library Catalog MARC data (Barton) and still seem to have the result online [5]. So perhaps just using the Barton data is the quickest way to begin playing with what once was MARC data as RDF? To my knowledge Stefano Mazzocchi simply created an RDF vocabulary that mirrors the MODS XML Schema, but I haven't looked at it in a while. Another thing worth checking out might be Rob Styles work [6] with other people at Talis at converting MARC with full fidelity to RDF. Perhaps he has some tools (or data) at his disposal? Rob you are on here right? I'd be willing to lend a hand with some of this if necessary, so just let me know if you think I can help. //Ed [1] http://www.indexdata.com/yaz/doc/yaz-marcdump.tkl [2] http://www.loc.gov/standards/marcxml/xslt/MARC21slim2RDFDC.xsl [3] http://www.loc.gov/standards/mods/v3/MARC21slim2MODS3.xsl [4] http://simile.mit.edu/wiki/MARC/MODS_RDFizer [5] http://simile.mit.edu/wiki/Dataset:_Barton [6] http://events.linkeddata.org/ldow2008/papers/02-styles-ayers-semantic-marc.pdf-- ----------------------------------- Karen Coyle / Digital Library Consultant kco...@kcoyle.net http://www.kcoyle.net ph.: 510-540-7596 skype: kcoylenet fx.: 510-848-3913 mo.: 510-435-8234 ------------------------------------
-- Corey A Harper Metadata Services Librarian Bobst Library, B42-LL1 New York University 70 Washington Square South New York, NY 10012 212.998.2479 corey.har...@nyu.edu