Re: Another example of Wikidata + schema.org for type enumerations

Dear Stéphane:

In addition to my last email:
> It's unfortunate that additionalType has such prominence on the schema.org definition, I think that's what's confusing people. 
I think it confuses more people on this list than typical users of schema.org. Multi-typed entities are an advanced case. It is not too prominent on https://productforums.google.com/forum/.


Best wishes / Mit freundlichen Grüßen

Martin Hepp

On 25 Feb 2014, at 03:16, Stéphane Corlosquet <scorlosquet@gmail.com> wrote:

> 
> 
> 
> On Mon, Feb 24, 2014 at 8:39 PM, Jarno van Driel <jarno@quantumspork.nl> wrote:
> Well for me the confusement started with a remark of GuHa: "additionalType == typeOf" (http://lists.w3.org/Archives/Public/public-vocabs/2013Oct/0136.html).
> 
> Which got me to think that in case of additionalType one could write:
> <link itemprop="additionalType" href="http://schema.org/Type1 http://schema.org/Type2">
> 
> Although Stéphane's remark: "href can only include one single URI" and Martin's remark: "the type in here is a property value" do make perfect sense from an HTML perspective. 
> 
> Now I looked at Dan's link to http://www.w3.org/TR/rdfa-syntax/#A-href and I've also looked it up in the Microdata specifications (http://www.w3.org/TR/2013/NOTE-microdata-20131029/#values) and one could argue that they do indicate a single URI. All be a bit technocratic. So IMO I think it would be a good thing it schema.org could explain this a bit more 'readable'.
> 
> I hope my previous email shed more light on this. 
> 
> It's unfortunate that additionalType has such prominence on the schema.org definition, I think that's what's confusing people. It's the first property for all types due to the alphabetical order and it belongs to Thing, while strictly speaking, it doesn't belong to the schema. You don't need additionalType in many cases, because you can just add as many types as you need in @typeof and @itemtype (with the limitation that all have to belong to the same vocab  for @itemtype). additionalType is a property that was introduced to work around a limitation of microdata, but now I'm wondering if it's causing more confusion than anything else. Could we bury it further down in the list? Looking at the discussions that led to the introduction of additionalType to schema.org [1], it was essentially to support the Good Relations use case in microdata where you have a main product type from the GR namespace and a more specific type from another namespace such as  http://www.productontology.org/id/Laser_printer. The microdata syntax doesn't allow this natively (while RDFa does).
> 
> Steph.
> 
> [1] http://lists.w3.org/Archives/Public/public-vocabs/2012Jun/0031.html
>  
> 
> 
> On Tue, Feb 25, 2014 at 2:24 AM, Thad Guidry <thadguidry@gmail.com> wrote:
> This is probably going to be a FAQ question over and over and over...so..
> 
> We should probably annotate when something takes multiple values within the schema somehow... hmmm.... something like... "only single value allowed"  or  "doesn't support multiple values".
> 
> Or is there already a hard and fast rule here in the schema... that only Types can take multiple values ?
> 
> Thoughts ?
> 
> -- 
> -Thad
> +ThadGuidry
> Thad on LinkedIn
> 
> 
> 
> 
> -- 
> Steph.

Received on Tuesday, 25 February 2014 10:33:49 UTC