There is work underway of aligning schema.org with http://purl.org/goodrelations/, which provides many of the additional features you suggest. For now, you can always attach the respective additional GoodRelations properties to the schema.org type as long as you use the full (!) property URL. See below for examples.
> * Product.productID
>
> First, the documentation could be improved by listing the possible content colon values. The current example given for http://schema.org/Product is <meta itemprop='productID' content='isbn:123-456-789'/>. Presumably other common content prefixes such as "upc:", "mpn:" and "asin:" are valid? Is there a difference between handling 12-digit UPC and 13-digit UPC/EAN?
>
> It would also be useful to promote the productID to a Thing and give it an enumeration to handle cases where the value is actually displayed in HTML to avoid the use of an unnecessary meta tag and to leverage the other basic Thing properties. Ex.
>
> <div itemprop="productID" itemscope itemtype="http://schema.org/UPC">
> <span itemprop="name">1234567890123</span>
> <img itemprop="image" src="/upc/1234567890123-upc.png" />
> <link itemprop="url" href="http://i-wish-i-could-lookup-upc-like-this.org/1234567890123 />
> </div>
>
You can attach GTIN8, GTIN14, etc.:
<div itemscope itemtype="http://schema.org/Product" itemid="#model">
<span itemprop="name">ACME Colorvision 123</span>
<span itemprop="description">The ACME Colorvision 123 is the
leading-edge color TV from our company.</span>
GTIN14: <span itemprop="http://purl.org/goodrelations/v1#hasGTIN-14has">12345678901234</span>
GTIN8: <span itemprop="http://purl.org/goodrelations/v1#hasGTIN-8has">12345678</span>
</div>
You can also use GoodRelations to indicate links to accessories using
http://purl.org/goodrelations/v1#isAccessoryOrSparePartFor
Example: State that a certain remote is an accessory for a certain TV set.
<div itemscope itemtype="http://schema.org/Product" itemid="#tvset">
<span itemprop="name">ACME Colorvision 123</span>
<span itemprop="description">The ACME Colorvision 123 is the
leading-edge color TV from our company.</span>
GTIN14: <span itemprop="http://purl.org/goodrelations/v1#hasGTIN-14has">12345678901234</span>
<link itemprop="http://purl.org/goodrelations/v1#isAccessoryOrSparePartFor" href="#remote" />
</div>
<div itemscope itemtype="http://schema.org/Product" itemid="#remote">
<span itemprop="name">ACME Remote Control</span>
<span itemprop="description">The ACME Remote Control is the handiest remote on the market.</span>
</div>
> * Offer::RentalOffer
>
> A subclass of Offer that distinctly represents a rental, rather than a purchase price. Should probably have both availableFrom and availableUntil dates - ex. use case: Netflix Instant rentals that have a limited window of availability that expires at a certain point. Somewhat more complicated, there is the concept of a price being assigned to a rental timespan and overage - ex. Rebox charging $1.50 per day or Blockbuster charging $5 for 3 days and $2 for each additional day past 3.
Use the GoodRelations business function property
http://purl.org/goodrelations/v1#hasBusinessFunction
with http://schema.org/Offer:
Example:
<div itemscope itemtype="http://schema.org/Offer" itemid="#offer">
<div itemprop="name">Rent a Volkswagen Golf V</div>
<div itemprop="description">blabla</div>
<link itemprop="http://purl.org/goodrelations/v1#hasBusinessFunction"
href="http://purl.org/goodrelations/v1#LeaseOut" />
... other offer properties follow here
</div>
The following business functions are pre-defined:
http://purl.org/goodrelations/v1#ConstructionInstallation
http://purl.org/goodrelations/v1#Dispose
http://purl.org/goodrelations/v1#LeaseOut
http://purl.org/goodrelations/v1#Maintain
http://purl.org/goodrelations/v1#ProvideService
http://purl.org/goodrelations/v1#Repair
http://purl.org/goodrelations/v1#Sell (default)
For respective pricing details, you can use the full power of
http://purl.org/goodrelations/v1#UnitPriceSpecification
A simple example: Car Rental: 25 USD / day plus 1 USD per mile
Example:
<div itemscope itemtype="http://schema.org/Offer" itemid="#offer">
<div itemprop="name">Rent a Volkswagen Golf V</div>
<div itemprop="description">blabla</div>
<link itemprop="http://purl.org/goodrelations/v1#hasBusinessFunction"
href="http://purl.org/goodrelations/v1#LeaseOut" />
Price: <div itemprop="http://purl.org/goodrelations/v1#hasPriceSpecification" itemscope
itemtype="http://purl.org/goodrelations/v1#UnitPriceSpecification">$
<span itemprop="hasCurrencyValue">25</span>
<meta itemprop="hasCurrency" content="USD">
<meta itemprop="hasUnitOfMeasurement" content="DAY"> per day
<time itemprop="validThrough" datetime="2012-12-31T23:59:59Z"></time>
</div> plus
<div itemprop="http://purl.org/goodrelations/v1#hasPriceSpecification" itemscope
itemtype="http://purl.org/goodrelations/v1#UnitPriceSpecification">$
<span itemprop="hasCurrencyValue">1</span>
<meta itemprop="hasCurrency" content="USD">
<meta itemprop="hasUnitOfMeasurement" content="1A"> per mile
<time itemprop="validThrough" datetime="2012-12-31T23:59:59Z"></time>
</div>
... other offer properties follow here
</div>
Note that the UN/CEFACT Common Code for "day" is "DAY", that for "car mile" is "1A". Also note that the gr:BusinessFunction for rental is gr:LeaseOut.
More examples, still to be converted to Microdata syntax (currently in RDFa) are here:
http://www.ebusiness-unibw.org/wiki/GoodRelationsPricing
I think this illustrates very well the potential of combining the granularity of GoodRelations with the generic schema.org elements.
I hope you find this useful.
Note that you can use those patterns IMMEDIATELY, even while the formal alignment between GoodRelations and schema.org is still underway.
Note further that the additional properties may have the important effect of indicating relevance / ranking criteria and additional meta-data to the search engines, even if you do not see an immediate effect in the rich snippets / rich captions. See also
http://wiki.goodrelations-vocabulary.org/GoodRelations_for_Semantic_SEO
Best wishes
Martin Hepp
--------------------------------------------------------
martin hepp
e-business & web science research group
universitaet der bundeswehr muenchen
e-mail: he...@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
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* Project Main Page: http://purl.org/goodrelations/