Re: .htaccess a major bottleneck to Semantic Web adoption / Was: Re: RDFa vs RDF/XML and content negotiation

So if this "hidden div / span" approach is not feasible, we got a problem.

The reason is that, as beautiful the idea is of using RDFa to make a) 
the human-readable presentation and b) the machine-readable meta-data 
link to the same literals, the problematic is it in reality once the 
structure of a) and b) are very different.

For very simple property-value pairs, embedding RDFa markup is no 
problem. But if you have a bit more complexity at the conceptual level 
and in particular if there are significant differences to the structure 
of the presentation (e.g. in terms of granularity, ordering of elements, 
etc.), it gets very, very messy and hard to maintain.

And you give up the clear separation of concerns between the conceptual 
level and the presentation level that XML brought about.

Maybe one should tell Google that this is not cloaking if SW meta-data 
is embedded...

But the snippet basically indicates that we should not recommend this 


Kingsley Idehen wrote:
> Mark Birbeck wrote:
>> Hi Martin,
>>> b) download RDFa snippet that just represents the RDF/XML content 
>>> (i.e. such
>>> that it does not have to be consolidated with the "presentation 
>>> level" part
>>> of the Web page.
>> By coincidence, I just read this:
>>   Hidden div's -- don't do it!
>>   It can be tempting to add all the content relevant for a rich snippet
>>   in one place on the page, mark it up, and then hide the entire block
>>   of text using CSS or other techniques. Don't do this! Mark up the
>>   content where it already exists. Google will not show content from
>>   hidden div's in Rich Snippets, and worse, this can be considered
>>   cloaking by Google's spam detection systems. [1]
>> Regards,
>> Mark
>> [1] 
>> <> 
> Martin/Mark,
> Time to make a sample RDFa doc that includes very detailed GR based 
> metadata.
> Mark: Should we be describing our docs for Google, fundamentally? I 
> really think Google should actually recalibrate back to the Web etc..

martin hepp
e-business & web science research group
universitaet der bundeswehr muenchen

phone:   +49-(0)89-6004-4217
fax:     +49-(0)89-6004-4620
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skype:   mfhepp 
twitter: mfhepp

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Received on Saturday, 27 June 2009 08:00:33 UTC