- From: Jarno van Driel <jarno@quantumspork.nl>
- Date: Mon, 19 May 2014 21:34:36 +0200
- To: "martin.hepp@ebusiness-unibw.org" <martin.hepp@ebusiness-unibw.org>
- Cc: Laura Dawson <Laura.Dawson@bowker.com>, Vicki Tardif Holland <vtardif@google.com>, W3C Web Schemas Task Force <public-vocabs@w3.org>
- Message-ID: <CAFQgrbYTsCpBLW9YyC3hLz-eAk-0C_aZppWP4SqRk3bGtqmbdQ@mail.gmail.com>
I was wondering if the @hasPart property from the "WebSchemas/Periodicals, Articles and Multi-volume Works" proposal could be a solution to link non-CreativeWork items to a CreativeWork and/or MediaObject? On Wed, Apr 9, 2014 at 9:23 AM, martin.hepp@ebusiness-unibw.org < martin.hepp@ebusiness-unibw.org> wrote: > On 08 Apr 2014, at 18:44, Laura Dawson <Laura.Dawson@bowker.com> wrote: > > > That’s the job of any given ontology. In the book industry, we have a > number of relationships defined already. I’m pretty sure in other media > types those also exist, so as to communicate to vendors “this thing > replaces that thing; this thing is derived from that thing; this thing has > nothing to do with that thing”. That’s essential information that vendors > (e.g. Amazon and Apple) need to have. > > Well, I think the question in a *Web* ontology like schema.org is to find > a good balance between the specificity of the property/relationship types > (or type/class alike), and the ability of publishers to employ the > distinctions properly, which is constrained by at least > 1. their understanding of the definition of a property (or type/class), > 2. their existing data structures (in particular local schemas), and > 3. the fitness of the distinction to the context of the user (e.g. what is > a common distinction in the library context - like book copy vs. book title > - can be harder to understand and apply for users in other contexts - like > car model vs. actual car, service template vs. service instance etc.). > > So simply taking a set of relationship types from an existing standard is > not always the best choice. > > It really depends on > > 1. whether the degree of specifity is compatible with the local schemas of > existing databases (i.e. that site owners can populate them with ease), and > 2. whether the consumers of data (e.g. search engines) can reconstruct the > distinction from contextual information or other signals. > > If e.g. search engines can reconstruct a distinction from contextual > information or other signals, it is not necessary to encourage publishers > of data to spend resources on declaring the respective meta-data in mark-up. > > In a Web vocabulary like schema.org, we should thus focus on those > classes/types and properties that > > 1. are easy to apply reliably from existing data sources by typical site > owners and > 2. that cannot be reconstructed with ease by a consumer of the data (*). > > Since adding type and structural information to Web data has costs, we > should further center our efforts on such meta-data that > > 1. has a high information entropy (approximately: is useful, additional > information) and > 2. can be reliably provided by a large number of sites. > > RDF and its proponents made, IMO, the mistake that they also expected such > meta-data explicitly in the data representation that a client can often > reliably reconstruct from the data alone. For example, data types for > literals like the information that the literal "ABC123" is a string or that > "2014-04-09" is likely a date. (The former has been fixed in RDF 1.1, I > know ;-) ) > > Many Web ontologies on the contrary (and maybe even GoodRelations in some > of its branches) provide conceptual distinctions that cannot be reliably > applied by site owners, either due to fact that the distinctions require a > deep philosophical understanding, or because the existing databases > available for powering a Web site simply do not support the distinction. > > As for schema.org, I would say that as long as we are defining properties > for a single schema.org type or a small set of types, this problem is a > lesser issue, since the type provides context and people will more easily > understand even distinctions (like author vs. editor for a book). But when > we speak about properties at a more generic level, or even for Thing, we > need to be super-careful. > > Best wishes > > Martin > > (*) Of course, this depends on the power of the data consumer - Google et > al. can likely do way more with messy, partly structured data than a > smartphone app or browser extension. One untested and undeclared working > assumption of the Semantic Web advocates is that data on the Web can ever > be consumed in its raw form by relatively dumb clients. I have argued > elsewhere [1] that structured data in Web content is rather "proto-data" > that can be turned into usable data by heavy post-processing. > > [1] http://lists.w3.org/Archives/Public/public-vocabs/2013Oct/0293.html > > > ------------------------------------------------------- > martin hepp > e-business & web science research group > universitaet der bundeswehr muenchen > > e-mail: martin.hepp@unibw.de > 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/ > > > > > On 08 Apr 2014, at 18:44, Laura Dawson <Laura.Dawson@bowker.com> wrote: > > > That’s the job of any given ontology. In the book industry, we have a > number of relationships defined already. I’m pretty sure in other media > types those also exist, so as to communicate to vendors “this thing > replaces that thing; this thing is derived from that thing; this thing has > nothing to do with that thing”. That’s essential information that vendors > (e.g. Amazon and Apple) need to have. > > > > From: Vicki Tardif Holland <vtardif@google.com> > > Date: Tuesday, April 8, 2014 at 11:52 AM > > To: Jarno van Driel <jarno@quantumspork.nl> > > Cc: "martin.hepp@ebusiness-unibw.org" <martin.hepp@ebusiness-unibw.org>, > W3C Web Schemas Task Force <public-vocabs@w3.org> > > Subject: Re: Why is the video property bound to creative work? > > Resent-From: <public-vocabs@w3.org> > > Resent-Date: Tuesday, April 8, 2014 at 11:52 AM > > > > My fear is that a "related" property would lead to confusion between > authors and consumers. For example, if we had a VideoObject related to > Barack Obama, does he appear in the video? Does the video discuss him? Is > it about a book he wrote? > > > > While we can know there is a relationship, it is difficult to understand > what that relationship is. > > > > - Vicki > > > > > > Vicki Tardif Holland | Ontologist | vtardif@google.com > > > > > > > > On Tue, Apr 8, 2014 at 11:42 AM, Jarno van Driel <jarno@quantumspork.nl> > wrote: > >> "The type of the object of this statement would then indicate the > nature of the relatedness, e.g. a VideoObject." > >> Says it all for me. In my mind this makes perfect sense, does anybody > have any extra input on this from a data-consumer perspective maybe? > >> > >> > >> > >> > >> On Tue, Apr 8, 2014 at 5:19 PM, martin.hepp@ebusiness-unibw.org < > martin.hepp@ebusiness-unibw.org> wrote: > >>> Thanks! The "related" property could also be used to link related > products in shop applications, btw. > >>> > >>> Of course, the exact semantics of the properties is pretty broad, but > we can leave it up to the consumers of the data to interprete it, imo. > >>> > >>> Martin > >>> > >>> > >>> > >>> > >>> On 08 Apr 2014, at 17:06, Jarno van Driel <jarno@quantumspork.nl> > wrote: > >>> > >>> > In this particular case a having 'related' property would already > suffice for what I'm looking to do. My issue isn't so much with having > multiple root entities relate to each other - which indeed adds additional > complexity and size of vocabulary - but more with the fact I can't have a > single Product (or MedicalProcedure for that matter) express it has a video > that adds additional info about the entity. > >>> > > >>> > But coming back to your idea for adding 'related' as a more generic > property of Thing for exactly this type of use, amongst others, seems like > a good idea to me. So I'm all for it. > >>> > > >>> > > >>> > On Tue, Apr 8, 2014 at 4:46 PM, martin.hepp@ebusiness-unibw.org < > martin.hepp@ebusiness-unibw.org> wrote: > >>> > I understand your point, but personally, I strongly discourage > having inverse properties, except for very few cases. Being able to model > the same fact from both sides using different properties adds confusion and > increases the size of the vocabulary. > >>> > > >>> > Martin > >>> > > >>> > > >>> > > >>> > On 08 Apr 2014, at 16:35, Jarno van Driel <jarno@quantumspork.nl> > wrote: > >>> > > >>> > > Thanks Martin, that helped a lot. > >>> > > > >>> > > Now putting the discussion about how multiple 'root' entities are > handled, by search engines and other data-consumers, aside for a moment. > (Although it might be a nice topic for new thread), I do want to re-use you > code for a moment to illustrate what's missing from my point of view, and > multiple root 'entites' serves quite nicely for this. > >>> > > > >>> > > Imagine a page has 2 'root' entities which aren't linked to the > WebPage by means of a property then I would use @itemid to have both > entities link to each other as such: > >>> > > > >>> > > <div itemid="video-object" itemscope itemtype=" > http://schema.org/VideoObject"> > >>> > > <link itemprop="about" href="product"> > >>> > > > >>> > > <h2>Video: <span itemprop="name">Video of the Personal SCSI > controller in use</span></h2> > >>> > > <meta itemprop="duration" content="T1M33S" /> > >>> > > <meta itemprop="thumbnail" content="personal-scsi-thumb.jpg" /> > >>> > > <object ...> > >>> > > <param ...> > >>> > > <embed type="application/x-shockwave-flash" ...> > >>> > > </object> > >>> > > > >>> > > <span itemprop="description">In this short video, we show how to > use the controller in typical setting.</span> > >>> > > </div> > >>> > > > >>> > > <div itemid="product" itemscope itemtype=" > http://schema.org/Product"> > >>> > > <link itemprop="video" href="video-object"> > >>> > > > >>> > > <span itemprop="name">The Personal SCSI Controller by ACME > Technology</span> > >>> > > <!-- other product properties go here --> > >>> > > </div> > >>> > > > >>> > > In this case both entities have a global identifier which should > make it possible to have both items link to each other. Now the VideoObject > points to the Product by means of <link itemprop="about" href="product"> > but I can't achieve this the other way around. In an ideal world <link > itemprop="video" href="video-object"> would achieve the same relation only > inversed but unfortunately Product doesn't have a 'video' property. > >>> > > > >>> > > Which could be resolved by either having 'video' be part of Thing > or having a completely new property like 'related' as you proposed. Either > way, there's something missing right now to provide this type of > relationship. > >>> > > > >>> > > > >>> > > > >>> > > > >>> > > > >>> > > On Tue, Apr 8, 2014 at 3:42 PM, martin.hepp@ebusiness-unibw.org < > martin.hepp@ebusiness-unibw.org> wrote: > >>> > > Hi Jarno: > >>> > > > >>> > > Below is how I would model a product video with the current set of > elements. > >>> > > In general I would suggest that if a use-case can be sufficiently > covered with existing elements, we rather encourage search engines to > implement support for the respective markup rather than adding redundant > conceptual elements that are there just because search engines prefer a > particular direction of a relationship. > >>> > > > >>> > > Example: Product with video: > >>> > > > >>> > > <div itemprop="video" itemscope itemtype=" > http://schema.org/VideoObject" itemref="product"> > >>> > > <h2>Video: <span itemprop="name">Video of the Personal SCSI > controller in use</span></h2> > >>> > > <meta itemprop="duration" content="T1M33S" /> > >>> > > <meta itemprop="thumbnail" content="personal-scsi-thumb.jpg" /> > >>> > > > >>> > > <object ...> > >>> > > <param ...> > >>> > > <embed type="application/x-shockwave-flash" ...> > >>> > > </object> > >>> > > <span itemprop="description">In this short video, we show how to > use the controller in typical setting.</span> > >>> > > </div> > >>> > > > >>> > > > >>> > > <div id="product"> > >>> > > <div itemprop="about" itemscope itemtype=" > http://schema.org/ProductModel"> > >>> > > <span itemprop="name">The Personal SCSI Controller by > ACME Technology</span> > >>> > > <!-- other product properties go here --> > >>> > > </div> > >>> > > </div> > >>> > > > >>> > > > >>> > > > >>> > > > >>> > > Best wishes / Mit freundlichen Grüßen > >>> > > > >>> > > Martin Hepp > >>> > > > >>> > > ------------------------------------------------------- > >>> > > martin hepp > >>> > > e-business & web science research group > >>> > > universitaet der bundeswehr muenchen > >>> > > > >>> > > e-mail: martin.hepp@unibw.de > >>> > > 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/ > >>> > > > >>> > > > >>> > > > >>> > > > >>> > > On 08 Apr 2014, at 15:10, Jarno van Driel <jarno@quantumspork.nl> > wrote: > >>> > > > >>> > > > "Conceptually, this is not true, since you can use itemref in > Microdata..." > >>> > > > > >>> > > > Would you be so kind to provide a small markup example, that > illustrates this. I think I understand what you mean but unfotunately > without an example I'm not sure if I understand you correctly. > >>> > > > > >>> > > > Op 8 apr. 2014 14:20 schreef "martin.hepp@ebusiness-unibw.org" < > martin.hepp@ebusiness-unibw.org>: > >>> > > > Conceptually, this is not true, since you can use itemref in > Microdata or a unique identifier in RDFa to make the video the outer > entitity in the nesting. > >>> > > > However, search engines have, in practice, two problems with > this: > >>> > > > > >>> > > > 1. Rich snippets and similar techniques often depend on finding > one main entity type, and use the outermost entities (root entities) in the > syntax for that task. So a Web page with a VideoObject and an Offer nested > therein may not trigger a product snippet because the search engine thinks > it was mainly a page about a video. > >>> > > > > >>> > > > 2. The linkage between entities on the basis of identifiers in > RDFa is, to my experience, not properly supported by major search engines, > so in reality, my proposed pattern will only work in Microdata. > >>> > > > > >>> > > > Martin > >>> > > > > >>> > > > > >>> > > > > >>> > > > On 08 Apr 2014, at 13:01, Jarno van Driel <jarno@quantumspork.nl> > wrote: > >>> > > > > >>> > > > > But of course you can also model it the other way round... > >>> > > > > > >>> > > > > True but only in cases where VideoObject is the main object. > When the main object is something else, which isn't part of the > CreativeWork branch, then there is no way to link a video by means of a > 'video' property. > >>> > > > > > >>> > > > > > >>> > > > > On Tue, Apr 8, 2014 at 10:33 AM, > martin.hepp@ebusiness-unibw.org <martin.hepp@ebusiness-unibw.org> wrote: > >>> > > > > In general, I am supportive of this, since any entity could > "have" a video. > >>> > > > > > >>> > > > > But of course you can also model it the other way round: > >>> > > > > > >>> > > > > http://schema.org/VideoObject > >>> > > > > ---> about --> Thing > >>> > > > > > >>> > > > > This works as of now. The main problem with the current > solution is that search engines seem to have a hard time honoring > information in that structure. And since we have the property "image" at > the level ofhttp://schema.org/Thing, why not promote video thereto, too? > >>> > > > > > >>> > > > > > >>> > > > > Martin > >>> > > > > > >>> > > > > > >>> > > > > On 08 Apr 2014, at 04:11, Jarno van Driel < > jarno@quantumspork.nl> wrote: > >>> > > > > > >>> > > > > > When working on markup for a MedicalProcedure I ran into the > issue of not having the 'video' property available to link an embedded > video, explaining the MedicalProcedure, to the entity. > >>> > > > > > > >>> > > > > > But while looking for a solution in the full list of types > at schema.org I started to wonder, wouldn't the 'video' property be > usefull on plenty of more types than just CreativeWork. For example a > 'video' about a person, organization, product, service or MedicalProcedure > is quite common, yet there's no way to link a video to any of those types. > >>> > > > > > > >>> > > > > > Of course the workaround for this would be an multi-type > entity as in "Product CreativeWork" but somehow that just feels wrong. > Looking at how much embedded video is used, wouldn't it be better if the > 'video' property moved up the chain and became part of 'Thing'? > >>> > > > > > >>> > > > > > >>> > > > > >>> > > > >>> > > > >>> > > >>> > > >>> > >> > > > >
Received on Monday, 19 May 2014 19:35:05 UTC