Re: [model] Clarifying annotation architecture

On Tue, Aug 4, 2015 at 10:58 AM, Randall Leeds <randall@bleeds.info> 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
assigned.

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
appropriate.


> 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

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