Re: [model] Clarifying annotation architecture

On Tue, Aug 4, 2015 at 10:58 AM, Randall Leeds <> wrote:

> If a system consumes an annotation with blank nodes and subsequently
> assigns then URIs, I don't see a problem.
Right, but I'm talking about reusing the resource after the URI has been

A system that wishes to annotate these resources would use the typical
> SpecificResource construction to avoid making open world statements about
> the originals.
But the resource-with-uri will have a motivation. So now where does the
motivation go once you have the SpecificResource? On the specific resource,
one assumes? And thus you have:

  "body": {
    "role": "tagging",
    "source": {
      "role": "commenting"
      "chars": "awesome"

So which role should I use here?

And when someone else just assumes (from the blank node pattern) that you
can add in roles at will you end up with

  "body": {
    "@id": "...",
    "role": ["tagging", "linking", "commenting"],
    "source": {
      "@id": "....",
      "role": ["commenting", "editing", "describing"]
      "chars": "awesome"

Which is unusable.

So, I see no problem at all with using blank nodes for the bodies as in
> Tim's example. In practice, I imagine that annotations with blank nodes
> might acquire URIs as they are shared and reproduced, but so what?
The worst case scenario is that two independent consumers assign different
> URIs, then subsequent statements about these have their relationship
> obscured.
No, the worst case scenario is when another annotation uses the resource
with the URI and assigns a different motivation to it.  Now the same
resource has multiple motivations, and you can't distinguish which is

> Anyway, isn't part of the purpose of an annotation data model to capture
> references not a priori uniquely identified by the publisher? If we really
> want to make a statement about a blank node, maybe the right move is to
> select it out of some more canonical reference? GraphPathSelector anyone? ;)
Have you tried selecting blank nodes out of a graph? ;)  And isn't the
point to *avoid* having to work with graphs? :)


Rob Sanderson
Information Standards Advocate
Digital Library Systems and Services
Stanford, CA 94305

Received on Tuesday, 4 August 2015 18:18:33 UTC