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Re: The perils and delights of multiple type entities for schema.org (was Re: Proposal: schema.org/MobileVideoGame)

From: Jarno van Driel <jarnovandriel@gmail.com>
Date: Sun, 15 Feb 2015 08:26:27 +0100
Message-ID: <CADK2AU2W0MHHqRtP3zgpfZmS4wiAS7UTCt9-VBqWfBTj=4n6iw@mail.gmail.com>
To: Aaron Bradley <aaranged@gmail.com>
Cc: Vicki Tardif Holland <vtardif@google.com>, Public Vocabs <public-vocabs@w3.org>
> "and the example posted by Jarno van Driel a year ago" & "Search engines
> do not provide visible support for MTEs."

I created a wiki page about this topic not long after my post Aaron
referred to, which I now also updated with an JSON-LD example:

2015-02-13 22:31 GMT+01:00 Aaron Bradley <aaranged@gmail.com>:

>    1. AFAIK, information for webmasters on how to express multiple type
>    entities (hereafter MTEs) is non-existent.  There's no documentation on the
>    subject on schema.org on itself nor, to the best of my knowledge, on
>    any of the sponsor's sites (neither Bing, Yahoo, Yandex nor Google provide
>    guidance in the use of MTEs).
>    The only way I've learned anything at all about correct MTE syntax is
>    via this mailing list, which is hardly a primary resource for most
>    webmasters.
>    All of this makes MTE use difficult for most webmasters, and increases
>    the chance that when MTEs are employed they'll be employed incorrectly.
>    2. Search engines do not provide visible support for MTEs.
>    I use the word "visible" because its by no means clear whether or not
>    the search engines correctly support MTE declarations, nor *which* search
>    engines understand MTEs.
>    The new Google Structured Data Testing Tool doesn't seem to support
>    MTEs well, and the example posted by Jarno van Driel a year ago still
>    returns errors that shouldn't be present if the MTE declarations were
>    understood correctly.  The Yandex Structured Data Validator throws an error
>    for the exact code provided for the mobile video game example I previously
>    referenced (from schema.org/VideoGame).
>    And while these are errors reported by specific data consumers, this
>    should concern schema.org IMO, and not just because the engines
>    referenced are schema.org sponsors.  These tools - and especially the
>    Google SDTT - are touchstones for webmasters wishing to employ structured
>    data, and when good markup requires the use of an MTE *and then* throws
>    a validation errors, webmasters are liable to produce inferior markup by
>    eradicating a type, or by abandoning their structured data efforts.
>    This does not support "the purpose of schema.org" to "improve the web
>    by creating a structured data markup schema supported by major search
>    engines", [2] especially when the major search engines give every
>    indication that they don't support the structured data markup webmasters
>    are being encouraged to use.
>    3. Use of MTEs makes it more difficult to extend the use of schema.org
>    (which the initiative also implicitly acknowledges as a goal in saying that
>    "Markup can also enable new tools and applications that make use of the
>    structure").
>    Would the sort of applications that have been worked on (e.g. [3],[4])
>    function with the additional complexity introduced by MTEs?  Don't know,
>    but they *do* add complexity.
> None of this is to say the use of MTEs isn't occasionally, or even often,
> warranted, and certainly not to say that they shouldn't be used.
> But it is to say that, as Martin Hepp has previously said on the subject
> [5] (and he's also enumerated some of the syntactical challenges of MTEs
> [6]), that there is "a trade-off decision" to be made here.  Yes, we don't
> want to - and quoting Martin again here - define "dozens of subtypes or
> additional siblings for existing types."  But it seems to me to be a
> reasonable trade off to create a sub-type when the entity class is question
> is widely represented on the web, and it is of no small significance in
> these cases whether or not a data consumer can accurately understand the
> data being provided - and I think mobile video games fall into that
> category.
> [1] https://lists.w3.org/Archives/Public/public-vocabs/2014Jan/0064.html
> [2] https://schema.org/docs/faq.html#0
> [3] http://moz.com/blog/semantic-analytics
> [4]
> http://apassant.net/2014/04/24/export-and-structure-your-musical-activity-with-schema-org/
> [5] https://lists.w3.org/Archives/Public/public-vocabs/2014Oct/0173.html
> [6] https://lists.w3.org/Archives/Public/public-vocabs/2014Jun/0052.html
> On Fri, Feb 13, 2015 at 12:20 PM, Vicki Tardif Holland <vtardif@google.com
> > wrote:
>> Out of curiosity, what limitations do you see in having to use multiple
>> types?
>> - Vicki
>> Vicki Tardif Holland | Ontologist | vtardif@google.com
>> On Fri, Feb 13, 2015 at 3:07 PM, Aaron Bradley <aaranged@gmail.com>
>> wrote:
>>> schema.org v1.92 introduced the new type VideoGame, a more specific
>>> type of both (the also-introduced) Game, and of SoftwareApplication.
>>> VideoGame is a great addition, but as mobile video games stand poised to
>>> overtake console-based games in popularity [1], there is no way
>>> differentiate between a traditional video game and this important variant.
>>> Freebase [2], Wikipedia [3] and Wikidata [4] all have entries for
>>> "mobile game", and the Google distinguishes between "Video game" [5] and
>>> "Mobile game" [6] in Knowledge Graph results generated on the basis of a
>>> video game title search.
>>> Perhaps most tellingly, schema.org itself gives a nod to the importance
>>> of mobile video games by providing a a markup example on the
>>> schema.org/VideoGame page.  And in my opinion the way in which this
>>> example is necessarily formulated demonstrates the utility of a
>>> MobileVideoGame type:
>>> <script type="application/ld+json">
>>> {
>>>   "@context": "http://schema.org",
>>>   "@type": ["VideoGame","MobileApplication"],
>>>   "gamePlatform":"iOS",
>>>   [...]
>>> }</script>
>>> Only by means of this multi-type entity declaration is a data consumer
>>> able to determine that a given video game is a mobile video game, and then
>>> only by inference - for those data consumers that are able to correctly
>>> process multi-type entities properly.
>>> In light of all of this, I propose MobileVideoGame, a more specific type
>>> of both VideoGame and MobileApplication.  No additional properties would be
>>> required to support this new type.
>>> Aaron Bradley
>>> Electronic Arts
>>> [1] http://fortune.com/2015/01/15/mobile-console-game-revenues-2015/
>>> [2] http://www.freebase.com/m/04951x
>>> [3] http://en.wikipedia.org/wiki/Mobile_game
>>> [4] http://www.wikidata.org/wiki/Q1121542
>>> [5] https://www.google.com/search?q=battlefield%204&pws=0&hl=en&num=10
>>> [6]
>>> https://www.google.com/search?q=simpsons%20tapped%20out&pws=0&hl=en&num=10
>>> [7]
>>> https://developers.google.com/structured-data/testing-tool/?url=http://jsbin.com/niqile
Received on Sunday, 15 February 2015 07:26:56 UTC

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