Because MARC is a key/value stream with a string-based encoding semantics, this does not justify a "direct mapping" to RDF. This is problematic.

From an implementor's view, a correct migration to RDF means to parse MARC records, map selected MARC-encoded values to functions/objects, evaluate contextual information and more semantic information from other sources (catalog codes, authority files), and let the mapping functions create RDF graphs with the transformed information in it, adding datatype information, links etc.

I invented something similar to your bfm proposal internally back in 2010.

https://wiki1.hbz-nrw.de/display/SEM/RDF-ISO2709+-+eine+RDF-Serialisierung+fuer+ISO+2709-basierte+bibliografische+Formate+%28MARC%2C+MAB%29

When asked for documenting the format, I hesitated and tried to describe it as an intermediate serialization format and called it "RDF/ISO2709". But the very bad side effect was that librarians who were not familiar with RDF and the semantics of RDF thought RDF was just a wrapper mechanism like XML, they called RDF a "format" and did not take it seriously as a modern graph model for the bibliographic data of future catalogs.

Karen picked up the idea 2011 in

http://lists.w3.org/Archives/Public/public-lld/2011Apr/0137.html

So, from my personal experience, I do not recommend to propose a MARC-centered "serialization only" Bibframe dialect. It will not improve Bibframe or ease the migration, it will just add a truncated RDF without links, without URIs, with another migration path.

If Bibframe can be seen as the "one-size-fits-all" RDF model for MARC, is another question. For much of the data I have, Bibframe is not my first choice. 

Jörg


On Sat, Jan 31, 2015 at 1:14 PM, Martynas Jusevičius <[log in to unmask]> wrote:
Jeff,

there is one reality, but it can be described in many different ways.
And yes, there should be a separate RDF vocabulary for each level.

Here's a completely fictional example to illustrate what I mean:

1. MARC-syntax level

_:record a bfm:Record ;
  bfm:recordType "Book" ;
  bfm:isbn "123456789" ;
  bfm:title "The Greatest Works" ;
  bfm:author1givenName "John" ;
  bfm:author1familyName "Johnson" ;
  bfm:author2givenName "Tom" ;
  bfm:author2familyName "Thompson" .

2. Linked Data level

<books/123456789#this> a bld:Work, bldtypes:Book ;
  dct:title "The Greatest Works" ;
  bld:isbn "123456789" ;
  bld:authors (<persons/john-johnson#this> <persons/tom-thompson#this>) .

<persons/john-johnson#this> a foaf:Person, bld:Author ;
  foaf:givenName "John" ;
  foaf:familyName "Johnson".

<persons/tom-thompson#this> a foaf:Person, bld:Author ;
  foaf:givenName "Tom" ;
  foaf:familyName "Thompson".


Both examples contain the same information, but it is encoded very
differently. Clearly the Linked Data style is preferred, and the MARC
vocabulary could in theory go away when there are no more legacy MARC
systems to support.

I haven't seen any actual MARC data, but if someone has a simple
example, we could work on that.

Martynas


On Sat, Jan 31, 2015 at 4:21 AM, Jeff Young <[log in to unmask]> wrote:
> Tim,
>
> The semantics behind MARC is based on reality. MARC cares (may) too much
> about which names and codes should be used in various structural positions,
> but there are real things lurking behind those.
>
> Jeff
>
>
>
> On Jan 30, 2015, at 9:58 PM, Tim Thompson <[log in to unmask]> wrote:
>
> Karen,
>
> Aren't the semantics behind MARC just the semantics of card catalogs and
> ISBD, with its nine areas of bibliographic description? ISBD has already
> been published by IFLA as a linked data vocabulary
> (http://metadataregistry.org/schema/show/id/25.html)--although, sadly, they
> left out the punctuation ;-)
>
> Tim
>
> --
> Tim A. Thompson
> Metadata Librarian (Spanish/Portuguese Specialty)
> Princeton University Library
>
> On Fri, Jan 30, 2015 at 9:01 PM, Young,Jeff (OR) <[log in to unmask]> wrote:
>>
>> What if it was two different vocabularies, rather than two different
>> levels of abstraction?
>>
>> There is only one reality. A rose by any other name would smell as sweet.
>> :-)
>>
>> Jeff
>>
>>
>>
>> > On Jan 30, 2015, at 8:02 PM, Martynas Jusevičius <[log in to unmask]>
>> > wrote:
>> >
>> > Karen,
>> >
>> > lets call those specifications BM (BIBFRAME MARC) and BLD (BIBFRAME
>> > Linked Data).
>> >
>> > What I meant is two different levels of abstractions, each with its
>> > own vocabulary and semantics. And a mapping between the two, for which
>> > SPARQL would be really convenient.
>> >
>> > In the 2-tier approach, these are the main tasks:
>> > 1. convert MARC data to RDF at the syntax level (BM)
>> > 2. design semantically correct bibliographic Linked Data structure (BLD)
>> > 3. define a mapping from BM to BLD
>> >
>> > So in that sense I don't think it is similar to profiles, as profiles
>> > deal with a subset of properties, but they still come from the same
>> > vocabulary.
>> >
>> > A somewhat similar approach is W3C work on relational databases:
>> > 1. direct mapping to RDF: http://www.w3.org/TR/rdb-direct-mapping/
>> > 2. customizable declarative mapping to RDF: http://www.w3.org/TR/r2rml/
>> >
>> >
>> > Martynas
>> > graphityhq.com
>> >
>> >> On Fri, Jan 30, 2015 at 10:15 PM, Karen Coyle <[log in to unmask]> wrote:
>> >> Martynas,
>> >>
>> >> I agree that the requirement to accommodate legacy MARC is a hindrance
>> >> to
>> >> the development of a more forward-looking RDF vocabulary. I think that
>> >> your
>> >> suggest of using SPARQL CONSTRUCT queries is not unlike the concepts of
>> >> selected views or application profiles -- where you work with different
>> >> subsets of a fuller data store, based on need.
>> >>
>> >> I wonder, however, how an RDF model designed "from scratch" would
>> >> interact
>> >> with a model designed to replicate MARC. I know that people find this
>> >> to be
>> >> way too far out there, but I honestly don't see how we'll get to "real"
>> >> RDF
>> >> if we hang on not only to MARC but to the cataloging rules we have
>> >> today
>> >> (including RDA). We'd have to start creating natively RDF data, and
>> >> until we
>> >> understand what that means without burdening ourselves with pre-RDF
>> >> cataloging concepts, it's hard to know what that means.
>> >>
>> >> All that to say that I would love to see a test implementation of your
>> >> idea!
>> >>
>> >> kc
>> >>
>> >>
>> >> On 1/30/15 9:03 AM, Martynas Jusevičius wrote:
>> >>
>> >> Hey,
>> >>
>> >> after following discussions and developments in the BIBFRAME space, it
>> >> seems to me that it tries to be too many things for too many people.
>> >>
>> >> I think many of the problems stem from the fact that (to my
>> >> understanding) BIBFRAME is supposed to accommodate legacy MARC data
>> >> and be the next-generation solution for bibliographic Linked Data.
>> >> Attempting to address both cases, it fails to address either of them
>> >> well.
>> >>
>> >> In my opinion, a possible solution could be to have 2 tiers of RDF
>> >> vocabularies:
>> >> - a lower-level one that precisely captures the semantics of MARC
>> >> - a higher-level one that is designed from scratch for bibliographic
>> >> Linked
>> >> Data
>> >>
>> >> The conversion between the two (or at least from the lower to the
>> >> higher level) could be expressed simply as SPARQL CONSTRUCT queries.
>> >>
>> >> Any thoughts?
>> >>
>> >>
>> >> Martynas
>> >>
>> >>
>> >> --
>> >> Karen Coyle
>> >> [log in to unmask] http://kcoyle.net
>> >> m: +1-510-435-8234
>> >> skype: kcoylenet/+1-510-984-3600
>
>