discussion of the Creative Commons Metadata work

[Andy Powell <a.powell AT ukoln.ac.uk>]

On Wed, 3 Dec 2003, Mike Linksvayer wrote:

> Andy Powell wrote:
> > (Note, the DCMI proposed recommendation for DC in XHTML (URL below)
> > recommends using DC.rights rather than DC.Rights as the value of the
> > name attribute).
>
> http://creativecommons.org/technology/metadata/extend updated accordingly.

Thanks.  However, I have some other comments about the text on this
page...

I've cut-and-pasted in part of the page text below, with my comments
interspersed.

> Use of the Dublin Core dc:rights element has long been fraught with
> confusion and misunderstanding. A study of its use in practice shows a
> variety of different purposes and formats with little commonality. For
> the Creative Commons metadata specification, we wanted to define a
> profile of the rights element that was more useful and structured.

So far, so good...

> Most copyright statements consist of a statement of the date and
> copyright holder (i.e. "(C) 2002 Gnomovision Records. All rights
> reserved.") and the actual text of the legal license. The date can be
> described using dc:date, the copyright holder using dc:rights and the
> license can be linked to with cc:license.

Note that the DC property dcterms:dateCopyrighted can be used to give an
explicit copyright date if you want.  dcterms:dateCopyrighted is a
sub-property of dc:date.

http://dublincore.org/documents/dcmi-terms/#dateCopyrighted

> We've decided to use dc:rights to hold a more structured description of
> the copyright holder. Here's an example:
>
> <dc:rights>
>   <Agent rdf:about="http://me.yoyo.dyne.name/";>
>     <dc:title>Yo-Yo Dyne</dc:title>
>     <dc:date>1001-10-01</dc:date>
>   </Agent>
> </dc:rights>
> As you can see the copyright holder is a person with a URL, a name and a
> date (of birth).

This isn't quite right.  There is no explicit mention of 'copyright'
anywhere in this RDF - dc:rights is defined as providing 'information
about rights held in and over the resource', not as providing 'information
about the copyright holder'.  Nor does the RDF say that the Agent is a
person.

So, what the RDF above actually says is something more like

The Agent with the dc:title Yo-Yo Dyne and a dc:date 1001-10-01 is
'information about rights held in and over the resource'.

As I've said before, I really find it hard to accept that a name and a
date on thier own (which is all we have in the RDF above) constitute
'information about rights held in and over the resource'.  Therefore, I
think this breaks the semantics of dc:rights.

But even if it doesn't break the semantics of dc:rights, it certainly
doesn't say all you want or claim it to be saying.

> In this way we cover all the parts of the copyright notice in a way that
> RDF tools can deal with. As a full example, this plain text statement:

> (C) 2002 Gnomovision Records. All rights reserved.
>
> This document has NO WARRANTY. You are permitted to
> copy it, modify it, and place up to three (3) copies
> of it on the White House lawn.
> becomes this chunk of RDF:
>
> <rdf:Description>
>   <dc:date>2002</dc:date>
>   <cc:license rdf:resource="http://flf.org/licenses/whiteHouseLawn"; />
>   <dc:rights><Agent>
>     <dc:title>Gnomovision Records</dc:title>
>   </Agent></dc:rights>
> </rdf:Description>
> Note: The actual text and description of the license ("...place up to
> three (3) copies...") is not included in this RDF, but would presumably
> be available at the URL given for the license.

Again, this RDF does *not* say the same as the plain text rights
statement.

- There is no indication that the year '2002' is the date of copyright.
- There is no indication that 'Gnomovision Records' are the copyright
  holders.

The use of cc:license to provide a CC URI is good :-).  I am hopeful that
DCMI will endorse a similar mechanism, probably in the form of a

dcterms:license

property, which will be defined as a sub-property of dc:rights.  I'll
report back if/when this is moved forward within DCMI.

Andy
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