RE: For review: Schema.org / Good Relations integration

Hi Dan,

Here's a place to start the discussion on support for rental offers.

"Offer" should be decomposed into several distinct types: sale offer of a product, sale offer of a service, and rental offer. At the moment, "Offer" is a sale offer of a product. We would suggest removing the "itemOffered" property from "Offer" and placing it on "ProductOffer", a subcategory of "Offer". The other subcategories of "Offer" are "RentalOffer" and "ServiceOffer".

Rental offer needs to have different kind of price, in particular, the price depends on the duration of the rental. It is possible to accommodate this by having a "duration" property on "RentalOffer" that would result in the inherited "price" property being interpreted as the rental price for the specified duration.

We are assuming that if the extension of Offer according to Martin's proposal is accepted, the new property of "priceSpecification" would exist alongside of the original "price" property and that webmasters would be encouraged to use one or the other, as appropriate. So, adding the "duration" property would work when the "price" property is being used.

If the webmaster wishes to use the new "priceSpecification" property, we would propose to create new "PriceSpecification" types, one of which would be a "RentalPriceSpecification", and this type would carry the "duration" property as well. 

A beneficial side effect of this approach would be that the "Offer" could contain multiple rental rates in the form of multiple instances of the "priceSpecification" property. This would not be possible when the webmaster chooses to use the "price" and "duration" properties of "RentalOffer" as we do not believe that it is a good idea to try to use matching sequences of price and duration values, because of the ease of creating errors in the page construction and editing processes.

A "RentalOffer" could be for use of a product. One can rent a car or a tool or a video camera or even a mobile phone for a period of time. However, one does not usually consider a hotel room, an apartment, or a seat on an airline flight to be a "Product". In these cases, some of the properties associated with both the existing and the proposed "Product" are not relevant. One solution would be to introduce a new category of things that can be rented but are not products. While satisfying semantically, we have had problems coming up with a simple term to label this category. Another solution would be to just reuse the existing "Product" and note that not all of the properties are appropriate for some things that can be rented. A discussion of this would be helpful to us.

We would propose to use the "itemOffered" property that is inherited by "RentalOffer" from "Offer" to designate the item being offered for rental. The range of this property could remain as "Product" or become something that is a supercategory of "Product" depending on the solution discussed in the preceding paragraph.

Rentals are at the top of our clients lists. Our clients are hotels, car rental agencies, airlines and rail transportation companies. While they also provide services, I would like to keep this note short and focused on rentals for now in order to get feedback. There is also a discussion that needs to happen about various existing and proposed properties, but I would like to postpone that discussion in order to determine if there is a willingness to consider including these rather small changes.

Thanks, Jim


-----Original Message-----
From: Dan Brickley [mailto:danbri@danbri.org] 
Sent: Friday, May 11, 2012 1:20 PM
To: Jim Rhyne
Cc: public-vocabs@w3.org; Martin Hepp (UniBW)
Subject: Re: For review: Schema.org / Good Relations integration

Hi Jim,

On 11 May 2012 22:07, Jim Rhyne <jrhyne@thematix.com> wrote:
> The additions and changes to schema.org will be a big help to our clients.

Glad to hear it!

> Unfortunately, support for rental transactions and service transactions is still omitted. There was some incomplete consideration of these types of transactions in the Good Relations ontology. A good many of our clients are travel providers, whose facilities are rented and whose services are purchased, so they are still left out of web markup.
>
> Is there any consideration to be given to extending the scope of this effort to include these types of transactions?

We're always interested in making schema.org markup more useful. I haven't looked in detail at the modeling required (or its treatment so far in GR). However travel has cropped up in a number of conversations recently, and seems an area well worth attention.

The approach we're taking here is to get the foundations in place and build things out gradually. So we shouldn't expect this round of additions to be the last word on the topic. If you can review the drafts with that in mind, it would be helpful to get your perspective on what more would be needed, and whether the basic building blocks are heading in the right direction.

In particular, we always benefit when discussions are grounded in practical examples, so if you're in a position to pass along some sample sites and specific pages whose existing content could be improved with additional schema.org markup, that would be really useful.

cheers,

Dan

Received on Friday, 11 May 2012 21:44:30 UTC