- From: Guha <guha@google.com>
- Date: Mon, 7 Oct 2013 20:54:52 -0700
- To: Karen Coyle <kcoyle@kcoyle.net>
- Cc: W3C Vocabularies <public-vocabs@w3.org>
- Message-ID: <CAPAGhv_0Fc40b=iiYoOevRvVv9SjfatA4KmXdxezSyrYWM0KHQ@mail.gmail.com>
Absolutely. The assumption is that if an entity is an instance of multiple types, this should be stated explicitly (as opposed to using a property from a different type and expecting a reasoner to infer the type). Guha On Mon, Oct 7, 2013 at 7:01 PM, Karen Coyle <kcoyle@kcoyle.net> wrote: > Something else that has made it hard for me to generalize from the use of > product ontology to the use of additional schema.org types is that the > product ontology use provides an additional type but no additional > properties. It feels kind of like an aside. The schema.org use case seems > to provide different capabilities, and has a more substantial impact on the > instance metadata. > > Admittedly, there was the quote that flew through here today saying that > proper reasoners would infer from the properties that one was making a > statement about additional types, but it does not seem that that assumption > has been in force during most of the development of schema.org -- > instead, multiple typing within schema.org has been done explicitly in > the design of classes and properties rather than being relegated to > instances and reasoners. > > kc > > > On 10/7/13 5:20 PM, Aaron Bradley wrote: > >> The documentation here leaves a lot to be desired. I think, at the very >> least, an example of this in use on schema.org <http://schema.org> with >> a schema.org <http://schema.org> URL would be useful. As far as I know >> >> ProductModel [1] is the only type that uses additionalType in example >> code, and this very much in keeping with what the property's description >> describes as the "typical" use for the property in "adding more >> specific types from external vocabularies in microdata syntax." >> >> Is <link> required to employ additionalType? Once an additionalType is >> declared, can properties be associated with it *and* the >> initially-declared item? There's no guidance on this or any other >> information on schema.org <http://schema.org> about implementing >> >> additionalType. >> >> Note that additionalType proposal [2] included "Changes to >> http://schema.org/docs/**datamodel.html<http://schema.org/docs/datamodel.html>" >> - namely the insertion of a >> section "Handling of Multiple Types." That section obviously never made >> its way to the Data Model page. >> >> [1] http://schema.org/ProductModel >> [2] http://www.w3.org/wiki/**WebSchemas/**additionalTypeProposal<http://www.w3.org/wiki/WebSchemas/additionalTypeProposal> >> >> >> >> On Mon, Oct 7, 2013 at 4:59 PM, Guha <guha@google.com >> <mailto:guha@google.com>> wrote: >> >> This is what http://schema.org/**additionalType<http://schema.org/additionalType>is for. >> >> All of an object's types have the same standing. >> >> guha >> >> >> On Mon, Oct 7, 2013 at 3:19 PM, Wes Turner <wes.turner@gmail.com >> <mailto:wes.turner@gmail.com>> wrote: >> >> Is this what http://schema.org/**additionalType<http://schema.org/additionalType>is for? >> >> -- >> Wes Turner >> >> >> On Mon, Oct 7, 2013 at 3:46 PM, Aaron Bradley >> <aaranged@gmail.com <mailto:aaranged@gmail.com>> wrote: >> >> Dan's solution and Martin's link are excellent ones. Just a >> quick FYI a previous discussion and a proposal related to it >> provide some further information on this type of conundrum >> in schema.org <http://schema.org>: >> >> http://lists.w3.org/Archives/**Public/public-schemabibex/** >> 2013Jan/0182.html<http://lists.w3.org/Archives/Public/public-schemabibex/2013Jan/0182.html> >> >> http://www.w3.org/wiki/**WebSchemas/**SchemaDotOrgMetaSchema<http://www.w3.org/wiki/WebSchemas/SchemaDotOrgMetaSchema> >> >> A fragment from the former reference: >> >> > Assuming they take OWL seriously, they would infer new >> types for the >> > entity if properties were mixed and matched. If example, if >> the claimed >> > type is schema:Book and somebody used the schema:sku >> property, they >> > could infer it is also a schema:Product. >> >> >> >> >> On Mon, Oct 7, 2013 at 1:37 PM, Dan Scott >> <dan@coffeecode.net <mailto:dan@coffeecode.net>> wrote: >> >> On Mon, Oct 07, 2013 at 09:16:01PM +0100, Chilly Bang >> wrote: >> >> Hello! >> >> i'm busy at the moment with marking up with >> microdata of an online bookstore and realized the >> following dilemma: >> if a page is about describing and selling of a >> CreativeWork/Book, so i come to selling properties >> with itemprop="offers" itemscope="" >> itemtype="http://schema.org/__**Offer<http://schema.org/__Offer> >> >> <http://schema.org/Offer>". But on this way i can't >> describe the book i sell like Product, with >> product's properties - i can't find any passage from >> CreativeWork to Product. There is in fact a passage >> from Offer to Product, with itemprop="itemOffered" >> itemscope="" itemtype="http://schema.org/__**Product<http://schema.org/__Product> >> >> <http://schema.org/Product>", but repeating isn't a >> good way, beside of this it isn't easy to get such >> passage into html, even with itemref. >> >> I see no possibility to go the way >> CreativeWork->Product->Offer (or >> CreativeWork->Product and CreativeWork->Offer), but >> only CreativeWork->Offer, or Product->Offer. >> CreativeWork can't be a Product or am i wrong? >> >> Imho CreativeWork surely can own product's >> properties so it must gladly have a passage from any >> CreativeWork property to Product. >> >> >> You can just use both types in the itemtype declaration, >> for example, >> itemtype="Book Product". >> >> We're doing this in the #schemabibex group to express >> offers for a given >> item. And Martin gave a wonderful example of this >> approach on this list >> just a few days back at >> http://lists.w3.org/Archives/_** >> _Public/public-vocabs/2013Sep/**__0206.html<http://lists.w3.org/Archives/__Public/public-vocabs/2013Sep/__0206.html> >> <http://lists.w3.org/Archives/** >> Public/public-vocabs/2013Sep/**0206.html<http://lists.w3.org/Archives/Public/public-vocabs/2013Sep/0206.html> >> > >> >> >> >> >> >> > -- > Karen Coyle > kcoyle@kcoyle.net http://kcoyle.net > m: 1-510-435-8234 > skype: kcoylenet > >
Received on Tuesday, 8 October 2013 03:55:20 UTC