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Re: Proposal: Audiobook

From: Wallis,Richard <Richard.Wallis@oclc.org>
Date: Thu, 26 Sep 2013 12:34:30 +0000
To: Martin Hepp <martin.hepp@ebusiness-unibw.org>
CC: Guha <guha@google.com>, Karen Coyle <kcoyle@kcoyle.net>, Dan Brickley <danbri@google.com>, "public-vocabs@w3.org" <public-vocabs@w3.org>
Message-ID: <F7BD8080-8915-4043-89E7-66E8D654B310@oclc.org>
I strongly recommend option #2, because
- it waives the need to define relevant combinations ex ante,
- it avoids the irritating listing of properties that are not relevant for most use cases, and
- it decouples the evolution of type combinations from the evolution of the schema.org<http://schema.org/> specification.

+1

1. to promote the use of multiple types at markup time rather than blowing up the schema.org<http://schema.org/> specification with explicitly defined types for these cases

+1


~Richard

On 26 Sep 2013, at 13:26, Martin Hepp <martin.hepp@ebusiness-unibw.org<mailto:martin.hepp@ebusiness-unibw.org>> wrote:

I strongly recommend option #2, because

- it waives the need to define relevant combinations ex ante,
- it avoids the irritating listing of properties that are not relevant for most use cases, and
- it decouples the evolution of type combinations from the evolution of the schema.org<http://schema.org/> specification.

>From the syntax, it is clear that Microdata and RDFa support multiple types in the aforementioned ways.

However, this decision touches the basis of the schema.org<http://schema.org/> data model. In essence, it drives schema.org<http://schema.org/> towards a collection of facets instead of a single, dominating type per each entity.

Thus, I asked for your review.

Some issues:
- If a property used in such a multiple type scenario, which type perspective on the entity does it refer to?
- If a property is defined differently for two types, which definition applies?
- Is the entity an instance of the union of both types or the intersection (I am not stupid: In RDF terms, it is clearly an instance of the union of both classes. But schema.org<http://schema.org/> is not strictly following the RDF model, as one can see from the definition of the schema.org<http://schema.org/>-specific domain and range semantics).

I do not think that these problems introduce actual problems for you as a consumer of the data, but they may introduce conceptual inconsistencies that could irritate adopters of schema.org<http://schema.org/>.

So for the moment, I suggest

1. to promote the use of multiple types at markup time rather than blowing up the schema.org<http://schema.org/> specification with explicitly defined types for these cases
Received on Thursday, 26 September 2013 12:35:02 UTC

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