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Re: Does google ignore hidden schema.org?

From: Martin Hepp <martin.hepp@ebusiness-unibw.org>
Date: Wed, 27 Feb 2013 10:42:03 +0100
Cc: Maury Markowitz <maury.markowitz@gmail.com>, public-vocabs@w3.org
Message-Id: <F90D74EE-7577-4BF7-9199-7A2AB5600046@ebusiness-unibw.org>
To: Adrian Giurca <giurca@tu-cottbus.de>
The quick answer is:

1. In general, search engines *prefer* data markup that is integrated with visible content, because that 
a) eases the use of certain information extraction techniques, which are valuable for them (e.g. learning from sites with markup about where to find information in other, similar sites that do not yet use data markup) and
b) helps, *to a certain degree*, to assess the credibility of the content (i.e. spotting markup spam).

2. However, coding advanced markup into existing HTML elements can be very, very complicated, so creating additional blocks with pure, invisible RDFa / Microdata data markup has many advantages. The full approach and the pros and cons are described in this paper:

Hepp, Martin; García, Roberto; Radinger, Andreas: RDF2RDFa: Turning RDF into Snippets for Copy-and-Paste, Technical Report TR-2009-01, 2009.
PDF at http://www.heppnetz.de/files/RDF2RDFa-TR.pdf

Search engines know that this "snippet style" of using RDFa has a lot of advantages over marking up visible content, mainly in terms of ease of coding and developing extensions that adds data markup to existing shop applications. But because of the bad experiences with hidden content in the past, being mainly used by spammers for black-hat SEO, they are very reluctant to openly advocate invisible markup.

The current status is that most major search engines perfectly accept invisible data markup on your page, unless your page has a questionable reputation or other indicators of the risk of manipulative SEO techniques. Many big and small shops successfully use invisible markup and get e.g. rich snippets in Google.

But they don't tell you that openly. From my experience, it is safe to assume that properly used RDFa in "snippet style", with otherwise empty HTML tags, is a valid approach and accepted by e.g. Google.

What you should avoid, though, are techniques for actively hiding the display of HTML elements that hold markup, e.g. with white text on white background, font-size of 1 pt., etc.

Hope that helps!

Best wishes

Martin Hepp



On Feb 27, 2013, at 10:19 AM, Adrian Giurca wrote:

> What would be the Google benefit if it can't understand the page structure?
> 
> -Adrian
> 
> On 2/26/2013 6:16 PM, Maury Markowitz wrote:
>> The ecommerce platform I'm using makes the addition of schema information to the body of the page somewhat difficult. It would have to be patched in in about a dozen places, and thus resistant to change.
>> 
>> It would be much simpler to make a new block (module) and simply include that on the page. However, blocks are normally visible, so it would look funny.
>> 
>> So what happens if I put schema information in a hidden div? Google normally ignores all hidden content, is that the case with schema too?
>> 
>> 
>> 
> 
> 

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

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Received on Wednesday, 27 February 2013 09:42:29 GMT

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