This is interesting work but it doesn't meet my goals. I want to see full support of RDA built into BIBFRAME, not as extensions. I don't want to get "pretty far" toward expression of relationship designators, I want full, transparent and easy expression of the full set of designators. Trying to infer relationships from higher level designators and genre codes is fraught when a work has multiple relationships.
Class proliferation is an unavoidable fact of BIBFRAME, given the design decision to avoid proliferation of properties. The bibliographic world is complex and we need either properties or classes to express the intellectual distinctions we make in our cataloging code. If we are not going to use properties, then let it be classes.
From: Bibliographic Framework Transition Initiative Forum [mailto:[log in to unmask]] On Behalf Of Steven Michael Folsom
Sent: Monday, October 23, 2017 10:55 AM
To: [log in to unmask]
Subject: Re: [BIBFRAME] Resource relationships
Absolutely; I think we’re describing the same observations. Select reuse of RDAU with the understanding that (as you said), the “same semantics may be inferred from the triple rather than being encoded in the property” was one of our goals.
This document describes our thinking from almost a year ago now, https://wiki.duraspace.org/display/LD4P/bibliotek-o?preview=/79795231/83237330/bibliotek-o_pattern_relations_201612.pdf.
It definitely involves using deeper parts of the RDA property hierarchies. Quoting from the doc:
“In the case of derivative and equivalence relationships this paper recommends the use of the unconstrained RDA properties, where RDA provides for a set of more granular subproperties. However, we recommend bf:references/bf:referencedBy over rdau:P60848 (“has referential relationship with”). The latter property is symmetric, and we see clear use cases (such as tracing a path of intellectual influence) where symmetry is not desirable. We will use BF 2.0 properties except for relationships that we can express with rdau:P60250 (“is derivative”) and rdau:P60191 (“has equivalent”) (and their subproperties) and proposed properties for relating events and works.Accompanying, sequential, and whole/part relationships will be addressed in other discussion papers and/or future work.”
A couple properties slipped in to our proposal that I would hope we move away from (like “adapted as choreography” should be replaced with the more general “adapted as”), but otherwise I think it still holds up. As you said, through testing these decisions can be tuned.
On 10/22/17, 1:13 PM, "Bibliographic Framework Transition Initiative Forum on behalf of Karen Coyle" <[log in to unmask] on behalf of [log in to unmask]> wrote:
thanks, Steven. This is along the lines of what I was suggesting. I note
in the LD4L document that you list the RDAU relationship properties
and sub-properties, e.g.
Label: is derivative
Definition: Relates a resource to a resource that is a modification of a
●rdau:P60115 "is modified by variation as"
●rdau:P60120 "is remade as"
●rdau:P60121 "is set to music as"
●rdau:P60177 "is abstracted in"
●rdau:P60178 "is indexed in"
●rdau:P60180 "is adapted as choreography"
Is LD4L using the full sub-property group? (Or potentially, could it?)
If so, that could go a long way to making more of a match between RDA
and BF in Joe's list, which only includes the higher level relationships.
Or, when you say: sticking to the general properties, do you mean only
the highest level, e.g. "is derivative"? Does your comment about
including resource types in properties as an "anti-pattern" include
properties like "is set to music as"? I think in a sense the rdau
property name is reflecting a range definition, and assumes perhaps a
point of validation for matching the relationship and the range. Is LD4L
taking a strict approach on that?
On 10/20/17 12:30 PM, Steven Michael Folsom wrote:
> In the LD4L analysis and adoption of BF2 we chose simply to extend BF2 using select RDAU properties. 
> RDAU isn’t perfect, but sticking to the general properties would get us pretty far. Our biggest reason for only using *select* RDAU properties is proliferation caused by the anti-pattern of minting new properties to account for the type of things being related; we don’t need “is opera adaptation of” if we have the more general “is adaptation of” and an Opera class/genre term.
> Similarly, using relationships to create new classes (as described in Joe’s bf:ChoreographicAdaption example below) causes unnecessary Class proliferation; each class would then require parallel classes for all the different types of relationships between resources.
> The other option being floated below (using bflc:Relationship) seems like over engineering for a problem that could be solved with just reusing the parts of RDAU that are well designed.
> Is this under consideration?
>  For more information on the LD4L analysis of BIBFRAME, see:
> - https://bibliotek-o.org/overview/overview.html
> - https://wiki.duraspace.org/display/LD4P/bibliotek-o
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