W3C home > Mailing lists > Public > public-vocabs@w3.org > June 2012

Re: additionalType property, vs extending Microdata syntax for multiple types

From: Martin Hepp <martin.hepp@ebusiness-unibw.org>
Date: Tue, 19 Jun 2012 23:02:20 +0200
Cc: Dan Brickley <danbri@danbri.org>, Peter Mika <pmika@yahoo-inc.com>, "jasnell@gmail.com" <jasnell@gmail.com>, "public-vocabs@w3.org" <public-vocabs@w3.org>, Ramanathan Guha <guha@google.com>, Jeni Tennison <jeni@jenitennison.com>
Message-Id: <CEBBB538-6A18-460B-891C-D16322654C09@ebusiness-unibw.org>
To: Egor Antonov <elderos@yandex-team.ru>
Hi Egor:


On Jun 19, 2012, at 10:53 PM, Egor Antonov wrote:

> Well, validators developers will not be very happy with this change.
Actually, I think they should be happy, because it makes their lives easier: They can now constrain the supported types for the main itemtype property to schema.org types while tolerating any URI for the additionalType/type property.

Otherwise, you cannot e.g. tolerate all http://www.productontology.org/ type URIs or the Volkswagen types from http://purl.org/coo/ns without maintaining a list of acceptable vocabularies.

> However, if it happens, I prefer 'type' name, because 'additionalType' implies there are other, non-additional ones.

I must admit that I prefer additionalType because it complements the main entity type as set by the itemtype keyword. But I am not religious about that.

> And on semantic level there must be no difference between object types.

The single semantic difference is that the additional itemtypes may come from any vocabulary of choice, while a schema.org-compliant client will typically only accept schema.org types for the main itemtype.

Martin

>  
> 19.06.2012, 22:37, "Martin Hepp" <martin.hepp@ebusiness-unibw.org>:
>> Hi Dan,
>> Thanks for summarizing this. Two suggestions:
>> 
>> 1. Instead of samePropertyAs: rdf:type, use owl:equivalentProperty if you want to express how the additional type information can be mapped into an RDF world.
>> 
>> 2. Add a link to the thread in the W3C archive so that the full details of the discussions are easy to reach:
>> 
>> By the way, the original proposal now being favored was already described in my post
>> 
>>     http://lists.w3.org/Archives/Public/public-html-data-tf/2011Oct/0088.html
>> 
>> and presented at the schema.org Workshop back in September 2011 (slide 16):
>> 
>> http://schemaorg.cloudapp.net/2011Workshop/sw1109_Vocabulary_GoodRelations.pdf
>> 
>> Best
>> 
>> Martin
>> 
>> 
>> On Jun 19, 2012, at 7:24 PM, Dan Brickley wrote:
>> 
>>  Thanks everyone. Lots of mail!
>> 
>>  I have tried to make a brief summary of some of the points in the Web
>>  Schemas wiki, just a sketch of individual positions really rather than
>>  a summary of the whole debate. I also started there to write up
>>  details of a concrete proposal for 'additionalType'.
>> 
>>  http://www.w3.org/wiki/WebSchemas/additionalTypeProposal ...
>> 
>>  Since nobody has volunteered to lead an effort to get Microdata syntax
>>  changed to support multiple types from different vocabularies, and on
>>  balance after reading thru all the debate, I think we should go for
>>  the new property approach.
>> 
>>  I'd like to make sure that we capture all the concerns people have in
>>  the Wiki and in the resulting property definition, and to give some
>>  thought to how validators and checkers ought to behave.
>> 
>>  Peter, Egor, others, ... can you live with a new property here? (one
>>  of 'additionalType' or 'type') Any preferences on name?
>> 
>>  cheers,
>> 
>>  Dan
>> --------------------------------------------------------
>> martin hepp
>> e-business & web science research group
>> universitaet der bundeswehr muenchen
>> 
>> e-mail:  hepp@ebusiness-unibw.org
>> phone:   +49-(0)89-6004-4217
>> fax:     +49-(0)89-6004-4620
>> www:     http://www.unibw.de/ebusiness/ (group)
>>          http://www.heppnetz.de/ (personal)
>> skype:   mfhepp 
>> twitter: mfhepp
>> 
>> Check out GoodRelations for E-Commerce on the Web of Linked Data!
>> =================================================================
>> * Project Main Page: http://purl.org/goodrelations/
>> 
>> 
> -- 
> Egor Antonov
> http://staff.yandex-team.ru/elderos

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

e-mail:  hepp@ebusiness-unibw.org
phone:   +49-(0)89-6004-4217
fax:     +49-(0)89-6004-4620
www:     http://www.unibw.de/ebusiness/ (group)
         http://www.heppnetz.de/ (personal)
skype:   mfhepp 
twitter: mfhepp

Check out GoodRelations for E-Commerce on the Web of Linked Data!
=================================================================
* Project Main Page: http://purl.org/goodrelations/
Received on Tuesday, 19 June 2012 21:02:53 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 19 June 2012 21:02:54 GMT