On 3/30/15 12:46 PM, Karen Coyle wrote:
[log in to unmask]" type="cite">Of course, applications do need to impose constraints on data. But having those constraints bundled with the meaning of the data elements greatly limits the flexibility of the metadata language. DC therefore has defined an "application profile" that is where the application-specific constraints (mandatory, repeatable) are defined. So you have maximum interoperability built into the definition of your metadata terms, and you still have the ability to customize the metadata "record" for your particular needs using an application profile.

Something else occurred to me after writing this, and it may not be obvious to others...

There is a significant difference between what the BIBFRAME vocabulary defines and the output from BIBFRAME programs. Because BIBFRAME is an RDF/OWL vocabulary, and because it does not define classes as disjoint, both of these are "valid" bibliographic statements based on the BIBFRAME vocabulary:

1.

ex:ResourceA
    bf:workTitle ex:AdventuresOfTomSawyer ;
    bf:hasInstance ex:ResourceB ;
    bf:creator lcna: n79021164 ;
    bf:language iso639-2:eng .

ex:ResourceB
     bf:providerDate "1996" ;
     bf:instanceOf ex:ResourceA ;
     bf:instanceTitle ex:TheAdventuresOfTomSawyer .


2.

    ex:ResourceC
        bf:creator lcna: n79021164 ;
        bf:workTitle ex:AdventuresOfTomSawyer> ;
        bf:language iso639-2:eng ;
        bf:instanceTitle ex:TheAdventuresOfTomSawyer> ;
        bf:providerDate "1996" .

In other words, the vocabulary does not determine that you must have a work "thing" and an instance "thing." It also does not have any say on whether properties are mandatory or repeatable. There is nothing in the vocabulary that would prevent you from having no work title, or a dozen work titles. This is inherent in RDF/OWL, which cannot enforce rules over a vocabulary, by its nature. Conversion of MARC records of course turns out bibliographic data consistent with what is in the MARC records (e.g. one 245). But the separation of properties into work and instance is a decision being made in the conversion programs. This means that there are rules being applied in the programs that process BIBFRAME records, but these rules are in addition to the BIBFRAME vocabulary, not part of it.

I don't recall any discussion of the rules that will be used in LC's implementation of the BIBFRAME vocabulary, but should this data become available on the open Web, only the essence of the vocabulary as defined in RDF/OWL will be applicable. It would be helpful to have clarity on the differences between the vocabulary and the implementation.

kc
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Karen Coyle
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