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Re: Re-usable bits/facets was: Re: aggregateRating and review under /Person

From: Martin Hepp <martin.hepp@ebusiness-unibw.org>
Date: Sat, 9 Feb 2013 12:35:37 +0100
Cc: public-vocabs@w3.org
Message-Id: <4C2301B6-6DD8-4E3D-BAE6-68437468D9CF@ebusiness-unibw.org>
To: kcoyle@kcoyle.net
Hi,
just from the top of my head: The data model behind schema.org supports two ways of using a property with multiple types:

First, properties are inherited along the type hierarchy, so subtypes share all properties with their supertypes.

Second, one can define the domain of a property to be the union of multiple types. So for instance, if the property xyz should be applicable with two types T1 and T2, it is not necessary to define a type T3 which is a common supertype of both. Instead, one can directly specify a list of types for which this property shall be available.

That is a nice deviation from the OWL semantics, where you have to define an implicit class for sharing a property.

This feature is currently visible only when you directly work on the schema and there is to my knowledge no tool support for managing this.

Best

Martin

On Feb 6, 2013, at 5:53 PM, Karen Coyle wrote:

> Matija, I do not have an answer to your question, but this brings up something that I have been meaning to address here for a while.
> 
> It would be good to look through schema.org for re-usable bits and/or facets that should be separated out from particular schemas for easy discovery and re-use. I am thinking of common elements like address, review, place, time, etc., that could conceivably combine with a wide variety of entities and that should be available to schema users as "universal add-ons" in their instance data.
> 
> In the library world our classification systems make use of "facets," some of which are entirely "free-floating" (e.g. can be used with any other term), and some of which are restricted to certain parts of the classification scheme. These are not added to the classification scheme as such but are only implemented in the assignment of classifications to particular items.
> 
> At the moment, schema.org takes a class/sub-class approach to sharing properties. This is not in conflict with the use of facets, and in fact library classifications combine hierarchical arrangement with the use of facets.
> 
> Exactly what should be a "facet" is hard to define theoretically, but a good clue is when the same elements or patterns begin to appear in separate schemas.
> 
> kc
> 
> On 2/6/13 1:35 AM, Matija Urh wrote:
>> Hi,
>> I'm building webpage and a stumble upon a problem.
>> I have three types of pages (artist, event and venue). The last two
>> (/Event and /Place) have "aggregateRating" and "review" properties, but
>> artist (i will use /Person) doesn't.
>> 
>> So what are my options? Googles Structured Data Testing Tool
>> <http://www.google.com/webmasters/tools/richsnippets> returns a
>> Warning.. Can I do this or is this bad for my SEO?
>> 
>> thx
>> 
>> 
>> -- matija urh
> 
> -- 
> Karen Coyle
> kcoyle@kcoyle.net http://kcoyle.net
> ph: 1-510-540-7596
> m: 1-510-435-8234
> skype: kcoylenet
> 

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

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Received on Saturday, 9 February 2013 11:36:03 GMT

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