W3C home > Mailing lists > Public > public-vocabs@w3.org > May 2014

Re: Enhancing PropertyValue-based data (was Re: Generic Property-Value Proposal for Schema.org)

From: Jarno van Driel <jarno@quantumspork.nl>
Date: Sun, 4 May 2014 00:05:42 +0200
Message-ID: <CAFQgrbbDToD-mQipr1s5=Q0oRfrtJf7wSsA19DLCac5jtZbQqQ@mail.gmail.com>
To: Francois-Paul Servant <francoispaulservant@gmail.com>
Cc: Martin Hepp <martin.hepp@ebusiness-unibw.org>, Niklas Lindström <lindstream@gmail.com>, W3C Web Schemas Task Force <public-vocabs@w3.org>
Sorry, should have been:

<div vocab="http://schema.org/" typeof="Product">
    ...
    <div property="additionalProperty" typeof="PropertyValue
http://acme.org/vocab/#Voltage" id="http://ex.com/ov_100_250">
    ...
    </div>
</div>

as opposed to:

<div itemscope itemtype="http://schema.org/Product">
    ...
    <div itemprop="additionalProperty" itemscope itemtype="
http://schema.org/PropertyValue" itemid="http://ex.com/ov_100_250">
    <link itemprop="sameAs" href="http://acme.org/vocab/#Voltage">
    ...
    </div>
</div>

And would this serve your purpose?


On Sat, May 3, 2014 at 11:29 PM, Jarno van Driel <jarno@quantumspork.nl>wrote:

> Forgive me if I misunderstand your point, but doesn't:
>
> <div vocab="http://schema.org/" typeof="Product">
>     ...
>     <div property="additionalProperty" typeof="PropertyValue
> http://ex.com/ov_100_250" id="http://ex.com/ov_100_250">
>     ...
>     </div>
> </div>
>
> get the same result as:
>
> <div itemscope itemtype="http://schema.org/Product">
>     ...
>     <div itemprop="additionalProperty" itemscope itemtype="
> http://schema.org/PropertyValue" itemid="http://ex.com/ov_100_250">
>     <link itemprop="sameAs" href="http://acme.org/vocab/#Voltage">
>     ...
>     </div>
> </div>
>
> Would the @propertyID still be needed then?
>
>
> On Sat, May 3, 2014 at 2:21 PM, Francois-Paul Servant <
> francoispaulservant@gmail.com> wrote:
>
>> Hi,
>>
>> what does it take to improve data published using PropertyValue, and to
>> share the enhancements?
>>
>> Le 2 mai 2014 à 22:37, martin.hepp@ebusiness-unibw.org a écrit :
>> <snip>
>>
>> Ideal Version: External Property with Qualitative Value
>>
>> <div itemscope itemtype="http://schema.org/Product">
>>  <span itemprop="name">ACME Electric Anvil</span>
>> ...
>>  Operating Voltage: <div itemprop="http://acme.org/vocab/#voltage"
>> itemscope
>>       itemtype="http://schema.org/QuantitativeValue">
>>      <span itemprop="minValue">100</span>-
>>      <span itemprop="maxValue">220</span>
>>      <meta itemprop="unitCode" content="VLT" > V
>> </div>
>>
>> with this
>>
>> Variant 1: Property name instead of URI
>>
>> <div itemtype="http://schema.org/Product">
>>  <span itemprop="name">ACME Electric Anvil</span>
>>  <div itemprop="additionalProperty" itemscope itemtype="
>> http://schema.org/PropertyValue">
>>   <span itemprop="name">Operating Voltage</span>
>>   <span itemprop="minValue">100</span>-
>>   <span itemprop="maxValue">250</span>
>>   <meta itemprop="unitCode" content="VLT"> V
>>  </div>
>> </div>
>>
>> or this
>>
>> Variant 2: Unit as text instead of UN/CEFACT Common Code and range as a
>> single field
>>
>>
>> <div itemtype="http://schema.org/Product">
>>  <span itemprop="name">ACME Electric Anvil</span>
>>  <div itemprop="additionalProperty" itemscope itemtype="
>> http://schema.org/PropertyValue">
>>   <span itemprop="name">Operating Voltage</span>
>>   <span itemprop="value">100-250</span>-
>>   <span itemprop="unitText">V</span>
>>  </div>
>> </div>
>>
>> or in worst case this:
>>
>> Variant 3: Range and Unit in a joint field
>>
>> <div itemtype="http://schema.org/Product">
>>  <span itemprop="name">ACME Electric Anvil</span>
>>  <div itemprop="additionalProperty" itemscope itemtype="
>> http://schema.org/PropertyValue">
>>   <span itemprop="name">Operating Voltage</span>
>>   <span itemprop="value">100-250 V</span>-
>>  </div>
>> </div>
>>
>>
>> It is obvious that the version with a dedicated property URI and a proper
>> http://schema.org/QuantitativeValue node is easier to process.
>>
>> But from a data provider's perspective, who typically has the product
>> properties in very light-weight property-value structures, with often
>> proprietary properties, even the step to Variant 1 makes data publication
>> much, much simpler, because he does not have to map the local property name
>> to a standard property URI nor determine the type of the value
>> (quantitative, qualitative, or Boolean). That is VERY difficult from
>> typical Web applications, even if the back-end systems (PDM/PIM) had this
>> additional data.
>>
>>
>>
>> one interesting exercise is to try to take data published in the
>> non-ideal variants, and to see what it requires to get to the ideal one.
>> With one constraint: we must imagine that there is already a lot of data
>> published in the non-ideal variants, and that we want to lift them without
>> republishing them all. This corresponds to the real situation of a client
>> or a third party who wants to make use of these data and share its results.
>> Or even of the publishing corporation, which may not be able without a lot
>> of work to change all the publishing process as it is (neither, of course,
>> to change anything to what has already been published). Is it possible to
>> publish some extra statements (in an independent, supplementary process) to
>> improve the non-ideal published data?
>> (In an ideal situation, we publish the data, and we can improve it
>> afterwards).
>>
>> Note that a player such as a search engine can quite easily handle the
>> situation: from
>> <span itemprop="name">Operating Voltage</span>
>> it can easily recognize the corresponding http://acme.org/vocab/#voltageproperty in its "knowledge graph of known entities and properties" and then
>> correctly index the product in question.
>>
>> What's for the rest of us?
>>
>> In the 3 variants that you describe, as they are, I think that there is
>> no way to efficiently publish improved data. One can use NLP techniques to
>> effectively use the data, but he/she cannot easily publish the results.
>>
>> The first reason is that the PropertyValue is not identified: in RDF
>> terms, it is a blank node. No way to say something about it (no way to lift
>> it therefore).
>> So, if I have, for instance, a small program that knows that a unitText
>> of "V" is equivalent to the unitCode "VLT", I can't simply publish
>> something that would lift data published in variant 2 to the level of
>> variant 1.
>>
>> On the other hand, if the data had been published using an identifier for
>> the PropertyValues, it would have been possible: if we had for instance
>> published in the first place:
>> <div itemtype="http://schema.org/Product">
>>    <span itemprop="name">ACME Electric Anvil</span>
>>    <div itemprop="additionalProperty" itemscope itemtype="
>> http://schema.org/PropertyValue" itemid="http://ex.com/ov_100_250">
>>            <span itemprop="name">Operating Voltage</span>
>>            <span itemprop="value">100-250</span>-
>>            <span itemprop="unitText">V</span>
>>    </div>
>> </div>
>>
>> one could simply state somewhere
>> http://ex.com/ov_100_250 schema:unitCode "VLT".
>>
>> to improve *all* the description of products published by ex.com that
>> have an operating voltage of 100-250.
>>
>> With that, variants 2, 3 4 are basically equivalent: one can use any ML /
>> heuristic technique to do the work, and easily share the results.
>> The publisher of the "non-ideal" data can keep its systems running as
>> they are, and just publish a small set of triples to improve all the
>> already published and the to-be-published data.
>>
>> Now, can we reach the "ideal version" state as easily?
>>
>> Yes, but it requires the use of the propertyID property:
>> <http://ex.com/ov_100_250> schema:propertyID <
>> http://acme.org/vocab/#voltage>
>> and to consider that, if the propertyID is the URI of a property, then if
>> s additionalProperty pv.
>> pv propertyID p.
>> then s p pv.
>> which is not completely in line with Martin's proposal.
>>
>> If this is a problem, there is a variant 0, which is an almost ideal
>> version
>> Variant 0: additionalProperty with External Type
>>
>> <div itemscope itemtype="http://schema.org/Product">
>>    <span itemprop="name">ACME Electric Anvil</span>
>>  ...
>>   Operating Voltage: <div itemprop="additionalProperty" itemscope
>> itemtype="http://acme.org/vocab/#Voltage <http://acme.org/vocab/#voltage>"
>> itemid="http://ex.com/ov_100_250">
>>        <span itemprop="minValue">100</span>-
>>        <span itemprop="maxValue">220</span>
>>        <meta itemprop="unitCode" content="VLT" > V
>> </div>
>> (possibly, add the propertyID to this markup)
>>
>> Note BTW that I do not consider the external property pattern as the
>> "ideal version":
>> - there will never be enough properties in a vocab: we need an
>> "additionalProperty" anyway
>> - it's sufficient to just define types of features in practical uses: if
>> you say that your product has (="additionalProperty") a given "Voltage", do
>> you really have to say that it "has voltage" the Voltage in question?
>> - it doesn't work well for "configurations" (partially defined products),
>> cf
>> http://events.linkeddata.org/ldow2013/papers/ldow2013-paper-11.pdf
>>
>> But this in another story. To summarize:
>> data published in "non-ideal" versions can be easily enhanced, and the
>> results shared, if and (I think) only if they include URIs for the
>> PropertyValue in the first place. In this case, publishing some statements,
>> independently of the original publishing, can improve a lot of data at once.
>> The use of URIs for PropertyValues - local ones  is fine - should
>> therefore be encouraged.
>>
>> (this assumes, of course, that users of the data make use of URIs and
>> conflate statements published about the same URI in two different places.
>> But without that, it's the whole idea of a web of data which is defeated.
>> This may seem obvious, but last time I checked Google's structured data
>> testing tool, it didn't do it even for statements in the same page.)
>>
>> fps
>>
>>
>
Received on Saturday, 3 May 2014 22:06:10 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:29:41 UTC