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Re: Play the Web » Blog Archive » Namespaces, Microformats, RDFa, HTML, XHTML

ging05 — Thu, 25 Jun 2009 07:54:27 -0000

Micro formats are little islands of ideas united into a federation by their consistent approach to markup.. But their consistencies don’t yield automatic discovery of unknown micro formats. .:)
Each one needs to be implemented and supported independently of the rest. ..

Re: RDFa Trials and Travails

ithoughts.de — Mon, 25 May 2009 15:15:43 -0000

Like this blog a lot ... thanks for sharing and giving such high quality links for RDFa.

Re: RDFa Trials and Travails

roblinton — Thu, 09 Oct 2008 17:31:31 -0000

Hi Ben,

Yes, I noticed the newer version, and that vocabularies are no longer mentioned in it. I whole-heartedly agree that vocabularies are an advanced topic and the primer might not be the best place to describe them, but I still think they need an entry point that's a little more accessible than what currently exists.

What I'd *love* to see is something along the lines of what I mention at the end of this post - a set of "gold standard" tools (validators and parsers) that developers can use to let them know that they're on the right track without needing to grok the entire RDFa specification.

I like the primer overall. I think it does a good job of showing the reason for RDFa and then gives just enough information to get a vague idea of the practice. You've no doubt come across this video tutorial which contains about the same level of information:
http://www.youtube.com/watch?v=ldl0m-5zLz4

But it's easy to digest... Oohh, flashing lights! ;)

I don't think we should underestimate the issue of accessiblity. I see RDFa as reaching out to the "normal" world from the somewhat-airy heights of RDF. It needs to be a welcoming handshake to bring people on board.

Cheers.

Re: RDFa Trials and Travails

Ben Adida — Wed, 08 Oct 2008 18:28:22 -0000

Hi Rob,

I just noticed that your link to the RDFa Primer is to a 1-year-old draft. Have you checked out the latest version:

http://www.w3.org/TR/xhtml-rdfa-primer/

It should be much simpler and easier to understand.

One important issue it does NOT address is the creation of new vocabularies, in part because that's a fairly advanced topic. That said, your feedback on the recent RDFa Primer would be super helpful.

Re: Play the Web » Blog Archive » Namespaces, Microformats, RDFa, HTML, XHTML

Paul Tarjan — Fri, 03 Oct 2008 01:55:38 -0000

Hey Rob,

Hope you enjoyed the talk :)

If you are worried about embedding in HTML instead of XHTML, then you can use eRDF ( http://research.talis.com/2005/erdf/wiki/Main/R... ) instead of RDFa.

We turn eRDF, RDFa, and uFormats into RDF without caring about how it got there. That way we don't have to pick a winner, everyone wins as long as the semantic web grows :)

Paul Tarjan
(|): Chief Technical Monkey :(|)

Re: RDFa Trials and Travails

roblinton — Mon, 29 Sep 2008 17:34:40 -0000

Thanks for those resources Michael, good links.

The vocabulary (or excuse me, ontology ;) that I've put together only adds a few terms so 80/20 theory holds true in our case. These added terms all revolve around describing different kinds of attribution; source, yes, but what nature of source? A copy? Derived work? Inspiration?

A shame to have just missed VoCampOxford. That would have been a wonderful trip.

Cheers,

Rob

Re: RDFa Trials and Travails

Manu Sporny — Thu, 25 Sep 2008 09:50:31 -0000

Hi Rob,

You do make a couple of fair criticisms:

* The RDFa Syntax Document is complex.
* We don't go into detail about creating vocabularies.
* Tools for performing vocabulary document validation are non-existent.

I just wanted to point out that the RDFa Syntax Document isn't meant for everyday web authors - it is meant for people that must have a specification for developing RDFa parsers. If all you want to do is re-use RDFa and you don't want to learn about how it works, the RDFa Syntax Document is not for you.

There is a community site meant to help people learn and understand RDFa, this is where we hope to put the more accessible content about RDFa:

http://rdfa.info/wiki

There are a couple of criticisms that you make, that are not accurate:

* Creative Commons should have re-used Dublin Core.
* Good RDFa validators/extractors do not exist.
* There is no way to currently do attribution trails.
* There needs to be a RDF to human-readable vocabulary conversion tool

There is a very good whitepaper that explains why CCrel was created:

http://cms.communia-project.eu/node/79

In a nutshell, they couldn't just re-use Dublin Core because it didn't have the properties that they needed. Take a look at their vocabulary (which is both machine readable and human readable):

http://creativecommons.org/ns#

Additionally, Creative Commons extended Dublin Core with their own vocabulary terms. This is a major feature in RDFa and the point shouldn't be lost. Creative Commons didn't have to talk to anybody to extend Dublin Core - innovation can happen in a distributed fashion instead of through a centralized standards process. Authoring web vocabularies is something that we haven't focused on yet, but will be detailed on the rdfa.info/wiki site. We had to focus on creating RDFa - the rest will come in time.

There are a couple of RDFa extractors and display programs for Firefox - Operator and Fuzzbot. Support for RDFa will get better in time. In the mean time, you can see a video of Fuzzbot in action here:

http://www.youtube.com/watch?v=oPWNgZ4peuI

You can create the attribution trails that you speak of by using dcterms:source from the Dublin Core Terms vocabulary. I believe it supports your use case:

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

Lastly, there does not need to be an RDFa vocabulary validation/display tool for people now that there is RDFa. Note that the Media, Audio, Video, Commerce, and CCrel vocabularies are all marked up using RDFa. This makes them RDF vocabularies that are human and machine readable:

http://purl.org/media/
http://purl.org/media/audio
http://purl.org/media/video
http://purl.org/commerce
http://creativecommons.org/ns#

Hope this helps - the learning curve for RDFa is steeper than we want it to be right now because there aren't many good tutorials out there. The concepts can be distilled fairly simply but we just haven't gotten much together just yet - we've been busy with creating RDFa. The next year or two will be focused on creating tools for RDFa and teaching it to web authors.

Thanks for your interested in RDFa and blogging about it - I hope some of the information above was helpful.

Re: RDFa Trials and Travails

Michael Hausenblas — Thu, 25 Sep 2008 02:36:42 -0000

Rob,

Fair criticism re vocabularies. In my experience it is about 80% reuse of existing vocabularies (or ontologies, if you need to impress you boss;) and only in few cases you need to invent terms on your own.

Please have a look at the following URIs and let me know in case you need more:

+ http://semanticweb.org/wiki/Onotlogies
+ http://esw.w3.org/topic/VocabularyMarket
+ http://www.schemaweb.info/ (not actively maintained)

Btw, a good way to develop vocabularies and or exchange thoughts would be a VoCamp (http://vocamp.org/wiki/Main_Page).

Cheers,
Michael

Re: RDFa Trials and Travails

Boris Mann — Wed, 24 Sep 2008 21:06:24 -0000

Very cool -- looking forward to talking about this. I have a personal love/hate relationship with microformats that lean mainly toward hate, and I've always suspected that RDFa land had some of the answers. Sounds like we need to bootstrap some example vocabularies?

Re: The need for an attribution trail

Ddonat — Thu, 28 Aug 2008 16:34:52 -0000

Another Missing Trackback from Victor Stone.

...Maybe because my background in software is in development tools and call me Abraham Maslow but this problems looks very much like a nail to me.

Attribution, on both ends, has to be brain dead simple. We’ve simplified it as much as we could at ccM (given my limited imagination for such things) with a search function during the content submission process. (In fact, the ‘Submit’ button is inactive until the artist posting the remix has attributed somebody ;))...

Re: The need for an attribution trail

Ddonat — Tue, 26 Aug 2008 13:52:00 -0000

Hi Karen,

Nice. You and Raul have the same approach, I think it is sound. It reads well and is clear to the reader how the content was sourced.

Re: The need for an attribution trail

Ddonat — Tue, 26 Aug 2008 13:51:02 -0000

Thanks Raul,

I think that language is very clear to readers.

Re: The need for an attribution trail

Ddonat — Tue, 26 Aug 2008 13:46:32 -0000

Thanks for the link Blaise, the original post by Danny O'Brien is excellent.

He is bang on with the statement:
"Nowadays, copying isn't always the core part of remunerative creative business. But accurate accreditation very much is."

This distinction is critical to understanding the copyright issues at hand.

Re: The need for an attribution trail

Ddonat — Tue, 26 Aug 2008 12:42:19 -0000

Lucas Gonze has a great response to this post.

He points out that "non-commercial users don’t care about copyright. They know zero about it." He has a point there and a number of my friends have said similar to me in the past.

He states "[I]n practice the issue of attribution only has a real-world impact for derived works created by commercial entities. Source works which are licensed to allow both derivative works and commercial use are the ones we’re talking about."

I agree this is the critical case. He also proposes a stack framework as mark-up for providing an attribution trail. Give it a read.

I have to check the Trackback settings for the site.

Re: The need for an attribution trail

Karen Murphy — Tue, 26 Aug 2008 11:27:23 -0000

At Strollerderby at Babble.com the policy was to credit the original source and then the secondary source. i.e.Photo Squeaky Marmot via Miss604. Linking to both.

Re: The need for an attribution trail

Blaise Alleyne — Tue, 26 Aug 2008 11:14:13 -0000

I think that makes a lot of sense. I don't have a particularly methodology for attributed my sources (yet), but my general approach is to link generously, to try and link back to anyone who helped me find the information I'm sharing.

In terms of the specific terminology though, I usually just use "via" if I'm referencing a middle-man... e.g. "Photo by Squeaky Marmot (via www.miss604.com)"

Also, this reminds me of a Techdirt post on the importance of attribution.

Re: The need for an attribution trail

Raul — Tue, 26 Aug 2008 10:40:56 -0000

David, et al

Guys, this is a great article. I wonder if we could do attribution as follows:

"Photo by Squeaky Marmot on Flickr. Originally seen on Miss604.com"

And then hyperlink to Squeaky Marmot's original Flickr photo and then Rebecca's article that links to this. I know that this requires a lot of work, but you guys are really touching on something key and relevant. Good stuff.

Re: Reusing Content: Derivative Work vs Modified Work

Kelli — Thu, 21 Aug 2008 19:02:05 -0000

Why make a distinction between modified and derivative work? Why not call it all modified or all derivative work?

Re: Reusing Content: Derivative Work vs Modified Work

Ddonat — Wed, 20 Aug 2008 15:12:13 -0000

Great insights, Blaise. Thanks.

From the link on Wikipedia, the way I read Transformative use would imply all of these images are transformative use. I too am no lawyer.

However, I am not trying to make a legal distinction. I'm more interested in content mark-up/metadata for content that is being reused. I think it is valuable to KNOW if a work I'm looking at is a derivative of another work. And although it may not be clear in my post, I'm trying to figure out:
1. If there are any hard rules for defining a work "Derivative". If so a system can define and then auto generate the metadata Work=Deriviative versus Work=Original. It seems to me that Derivative is likely a user generated field.

2. But there are easily defined rules for Modified work. However, is that useful metadata? Work=modified?

Re: Reusing Content: Derivative Work vs Modified Work

Ddonat — Wed, 20 Aug 2008 14:58:45 -0000

Hey Bryan,

Well, I actually agree. I am not advocating technology controls.

I am wondering if it would be useful for a technology to understand "Yes this is a Derivative work", but it seems to me that "derivative or not" must be a human input piece of metadata. Technology can't define a Derivative work.

However technology can determine if it is modified, and as such "Yes this is a modified work" could be a system generated piece of metadata.

Is it worth it to a content creator to know if content is modified or not?

Re: Reusing Content: Derivative Work vs Modified Work

Blaise Alleyne — Wed, 20 Aug 2008 14:28:57 -0000

In other words, I think you're inventing the distinction between modified and derivative works. That's not a legal distinction, to the best of my knowledge.

There is, however (at least in the US), a distinction between non-transformative and transformative derivative works.

Re: Reusing Content: Derivative Work vs Modified Work

Blaise Alleyne — Wed, 20 Aug 2008 14:27:25 -0000

I'm no lawyer,but I've taken an interest in this sort of thing.

All of those cases are clearly derivative works, except maybe image 3. The Creative Commons tends not to view a picture in a page of text as a derivative work, where as the Free Software Foundation (with the GNU Free Documentation License) believes that would constitute a derivative work. Which of them is right has yet to be seen, and would depend on the theories being tested in court. Or so I've been told.

I don't see how there's any question as to whether a cropped image is legally a derivative work. I think the real question you're asking is about transformative use. I think there's a strong argument that image 1 is transformative, whereas it would be harder to say the same about image 4. Image 3, if considered a derivative of the original, is also clearly transformative.

Re: Reusing Content: Derivative Work vs Modified Work

Bryan Rieger — Wed, 20 Aug 2008 14:26:26 -0000

Interesting question - but I'm not so sure this is a technology problem, but rather a cultural and/or legal one. IMO a technology solution to this would likely result in DRM being required on all hardware and software for this to work - which REALLY scares me.