Blank nodes (or anonymous nodes) are part of RDF and are not a problem at all. They are essential to build embedded resources. When the RDF graph moves physically (e.g. from triple store to triple store) they must get renumbered internally so the embedded resource is still valid at the other place, and can be continued to use in the new environment without internal graph node collisions.

These tasks are opaque to applications, they are part of RDF graph management of the RDF store implementor, and are not related or controllable by Bibframe.

All embedded resources can be turned into externally visible resources by assigning IRIs to them, if you want to avoid embedded resources. The result is often too verbose and does not look very concise, and in most cases, there is no requirement of doing that.

Jörg

On Tue, Nov 18, 2014 at 5:07 PM, Joseph Kiegel <[log in to unmask]> wrote:

There has been discussion of blank nodes earlier on the list, and perhaps agreement that there should be as few of them as possible. But we don't have a model where they are eliminated entirely.

I have a question about blank nodes in regard to BIBFRAME as a carrier.

In RDF 1.1 Concepts and Abstract Syntax, section 3.4, we find: "Blank node identifiers . are always locally scoped to the file or RDF store, and are not persistent or portable identifiers for blank nodes". A function of BIBFRAME, as a carrier, is to move linked data from one institution to another, that is, from one RDF store to another. Isn't it true, then, that blank node identifiers, which are valid at Library A, are not defined when they get to Library B? This seems like a problem.

Is the use of blank nodes consistent with BIBFRAME's function as a carrier?