Re: examples with blank nodes in prov-o html document

On Feb 12, 2013, at 2:59 PM, Luc Moreau <L.Moreau@ecs.soton.ac.uk> wrote:

> It would be nice to have Provo examples that can translate into well form provn and valid according to prov-constrains.

+1

> It's not the case now.

I disagree.

> With an explicit identifier for usage, it would be.

That blank node is identifiable. Why a concern about a bnode Usage and no concern for all of the bnode Influences?
They are all just resources; identify to your hearts content.
It seems that you are concerned about a "round trip" back to RDF not looking exactly like the starting point. That is the nature of the bnode, and shouldn't be cause for concern.

-Tim



> 
> --
> Professor Luc Moreau
> Electronics and Computer Science   tel:   +44 23 8059 4487
> University of Southampton          fax:   +44 23 8059 2865
> Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk
> United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
> 
> 
> ________________________________________
> From: Timothy Lebo [lebot@rpi.edu]
> Sent: 12 February 2013 6:26 PM
> To: Luc Moreau
> Cc: public-prov-wg@w3.org
> Subject: Re: examples with blank nodes in prov-o html document
> 
> Is there a problem to solve here?
> 
> Otherwise, I'm happy to let it drop.
> 
> Regards,
> Tim
> 
> On Feb 12, 2013, at 1:17 PM, Luc Moreau <L.Moreau@ecs.soton.ac.uk<mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
> 
> Hi Tim,
> 
> This would be your way of tackling the problem, but it's not a way that any PROV document
> has specified.
> That's why, from my point of view, this solution is not interoperable.
> 
> It is valid PROV-O, I agree, but without equivalent in the data model, since in this
> example, the derivation refers to a usage, and PROV mandates the presence of an identifier.
> 
> Luc
> 
> 
> On 12/02/13 18:08, Timothy Lebo wrote:
> 
> On Feb 12, 2013, at 12:07 PM, Luc Moreau <L.Moreau@ecs.soton.ac.uk<mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
> 
> 
> Hi Tim,
> 
> I don't know of a way to translate this rdf in an interoperable way
> 
> 
> (As I've said) I do; you mint an identifier.
> 
> 
> since we have not specified this in our specs.
> 
> It's for that reason I thought this example should be changed.
> 
> (are we still talking about https://dvcs.w3.org/hg/prov/file/5495d990f17b/testcases/provo/prov-o-property-hadUsage-PASS.ttl ?)
> 
> But, it's valid PROV-O. Why should it be changed?
> There's nothing special about the blank node other than it doesn't have a URI.
> It's still a legitimate resource. And any URI that you choose to identify that resource will do.
> 
> Are you still suggesting that this example change?
> 
> -Tim
> 
> 
> 
> Luc
> 
> On 02/12/2013 03:26 PM, Timothy Lebo wrote:
> On Feb 12, 2013, at 10:09 AM, Luc Moreau <L.Moreau@ecs.soton.ac.uk<mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
> 
> If we do, and convert back to rdf, we don't have an equivalent rdf representation.
> Yes, you would :-)
> 
> -Tim
> 
> 
> Professor Luc Moreau
> Electronics and Computer Science
> University of Southampton
> Southampton SO17 1BJ
> United Kingdom
> 
> On 12 Feb 2013, at 15:00, "Timothy Lebo" <lebot@rpi.edu<mailto:lebot@rpi.edu>> wrote:
> 
> On Feb 12, 2013, at 9:57 AM, Luc Moreau <L.Moreau@ecs.soton.ac.uk<mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
> 
> Dm/XML/prov-n require an explicit identifier which we don't have in this example.
> Why not make one up?
> 
> -TIm
> 
> Professor Luc Moreau
> Electronics and Computer Science
> University of Southampton
> Southampton SO17 1BJ
> United Kingdom
> 
> On 12 Feb 2013, at 14:54, "Timothy Lebo" <lebot@rpi.edu<mailto:lebot@rpi.edu>> wrote:
> 
> Luc,
> 
> On Feb 12, 2013, at 9:25 AM, Luc Moreau <L.Moreau@ecs.soton.ac.uk<mailto:L.Moreau@ecs.soton.ac.uk>> wrote:
> 
> The prov-o document has several examples with blank nodes.
> Some of them are difficult
> to express in prov-n/prov-xml.
> 
> Consider:
> https://dvcs.w3.org/hg/prov/file/5495d990f17b/testcases/provo/prov-o-property-hadUsage-PASS.ttl
> 
> The usage has no identifier we can use in the derivation.
> Any identifier will do; you may choose a new one for each bnode you find.
> 
> 
> Should we keep examples of this kind in the specification or should we introduce an explicit
> identifier for usage here?
> We are using blank nodes to help the reader focus on the structure of the PROV-O pattern.
> I think this is appropriate for the audience of PROV-O.
> 
> Perhaps it's just a matter of knowing how to handle bnodes when mapping to other serializations?
> We don't specify that. So, we don't  how express that example in prov-xml/prov-n.
> In XML, it'd be an element with no @id attribute (since, that's exactly what a blank node is).
> I haven't written any translators to XML or N, so I guess I don't understand the problem clearly enough.
> What is difficult about "filling something in" if it's not there?
> This is exactly the correct interpretation of a bnode.
> 
> Regards,
> Tim
> 
> 
> 
> 
> 
> --
> Professor Luc Moreau
> Electronics and Computer Science   tel:   +44 23 8059 4487
> University of Southampton          fax:   +44 23 8059 2865
> Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk<mailto:l.moreau@ecs.soton.ac.uk>
> United Kingdom                     http://www.ecs.soton.ac.uk/~lavm<http://www.ecs.soton.ac.uk/%7Elavm>
> 
> 
> 
> 
> 
> 
> --
> Professor Luc Moreau
> Electronics and Computer Science   tel:   +44 23 8059 4487
> University of Southampton          fax:   +44 23 8059 2865
> Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk<mailto:l.moreau@ecs.soton.ac.uk>
> United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
> 
> 
> 
> 
>

Received on Tuesday, 12 February 2013 20:23:38 UTC