- From: Martin Hepp <martin.hepp@unibw.de>
- Date: Thu, 22 Jan 2015 11:30:16 +0100
- To: "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
- Cc: Justin Boyan <jaboyan@google.com>, Simon Spero <sesuncedu@gmail.com>, W3C Web Schemas Task Force <public-vocabs@w3.org>, Dan Brickley <danbri@google.com>
On 22 Jan 2015, at 10:37, Peter F. Patel-Schneider <pfpschneider@gmail.com> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > So you want to be able to say that all value for a property on instances of > some class must already be known to belong to a particular type. There are > several systems for doing this in RDF already (SPIN, Stardog ICV, RDFUnit). > I don't know whether this would work well with the disjunctive ranges in > schema.org, however. > > I'm also not sure that universally enforced domain and range constraints are > a viable option. How would a constraint violation be handled? > The Google Structured Data Testing Tool could simply issue a warning. In fact I assume that the tool is now more or less based on the RDFa formalisation of schema.org. > > Guidance on popular types for developers could be handled by documentation. > Why make the formalism more complex for this? The exact purpose of the proposed rangeHint and domainHint properties is to capture such information for the documentation in the source code of the schema.org vocabulary. > > peter > > > On 01/21/2015 11:47 PM, Martin Hepp wrote: >> No, what we need are different forms of domain and range axioms: >> >> - database-style domain and range constraints so that a validator can >> spot contradictions and - guidance on popular types for domain or range >> so that developers find them. >> >> The second are not constraints and not local ranges, because an advanced >> user may still choose to use a type that is covered by the formal domain >> or range type (complex or atomic). We want to be able to say that >> formally, the range is Thing or something generic, but we want to help >> developers find the most likely subtypes without asking them to >> understand the full type hierarchy. >> >> Best >> >> Martin >> >> -------------------------------------------------------- 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 >> >> >> >> >> >> On 21 Jan 2015, at 18:28, Peter F. Patel-Schneider >> <pfpschneider@gmail.com> wrote: >> >> It seems to me that what is needed here is local ranges, e.g., the range >> of http://schema.org/itemListElement for numbered lists is a number. >> >> peter >> >> >> On 01/21/2015 08:51 AM, Justin Boyan wrote: >>>>> I like Martin's idea. We have the same issue with >>>>> http://schema.org/itemListElement , which can point to an arbitrary >>>>> Thing, but where it's important to call out the special type of >>>>> ListItem for numbered lists. >>>>> >>>>> On Wed Jan 21 2015 at 11:48:02 AM Simon Spero <sesuncedu@gmail.com >>>>> <mailto:sesuncedu@gmail.com>> wrote: >>>>> >>>>> The issue is somewhat complicated, in that the range is due to a >>>>> historical name collision. >>>>> >>>>> The only things which can have a purpose that is a >>>>> MedicalDevicePurpose are Medical devices. The only values of >>>>> purpose these devices can have are medical devices- >>>>> >>>>> (interArgIsa1-2 purpose MedicalDevice MedicalDevicePurpose) >>>>> >>>>> Simon >>>>> >>>>> On Jan 21, 2015 11:21 AM, "Martin Hepp" <martin.hepp@unibw.de >>>>> <mailto:martin.hepp@unibw.de>> wrote: >>>>> >>>>> Hi Dan, A hands-on solution would be to add two internal >>>>> "annotation" properties "rangeHint" and "domainHint" that allow >>>>> explicitly triggering the display of certain schema.org >>>>> <http://schema.org> types in the documentation. >>>>> >>>>> >>>>> <div typeof="rdf:Property" resource="http://schema.org/purpose"> >>>>> ... <span>Range: <a property="http://schema.org/rangeHint" >>>>> href="http://schema.org/MedicalDevicePurpose">MedicalDevicePurpose</a></span> >>>>> >>>>> >> >>>>> > <span>Range: <a property="http://schema.org/rangeIncludes" >>>>> href="http://schema.org/Thing">Thing</a></span> </div> >>>>> >>>>> >>>>> The documentation could then list the formal range (Thing) and >>>>> popular types for the range (e.g. MedicalDevicePurpose) >>>>> >>>>> This requires just ten lines in the RDFa and tweaking the Python >>>>> code and Jinja templates that generate the documentation. >>>>> >>>>> Martin >>>>> >>>>> -------------------------------------------------------- martin >>>>> hepp e-business & web science research group universitaet der >>>>> bundeswehr muenchen >>>>> >>>>> e-mail: martin.hepp@unibw.de <mailto:martin.hepp@unibw.de> phone: >>>>> +49-(0)89-6004-4217 <tel:%2B49-%280%2989-6004-4217> fax: >>>>> +49-(0)89-6004-4620 <tel:%2B49-%280%2989-6004-4620> www: >>>>> http://www.unibw.de/ebusiness/ (group) http://www.heppnetz.de/ >>>>> (personal) skype: mfhepp twitter: mfhepp >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> On 19 Jan 2015, at 18:18, Dan Brickley <danbri@google.com >>>>> <mailto:danbri@google.com>> wrote: >>>>> >>>>>> Hi Simon, >>>>>> >>>>>> Thanks for these! I've opened Github issues for most of them, >>>>>> though I take your point that there are more out there. >>>>>> >>>>>> On 18 January 2015 at 17:54, Simon Spero <sesuncedu@gmail.com >>>>> <mailto:sesuncedu@gmail.com>> wrote: >>>>>>> 1: The range of schema:purpose has no purpose. >>>>>>> MedicalDevicePurpose OR Thing = Thing >>>>>> >>>>>> https://github.com/schemaorg/schemaorg/issues/233 >>>>>> >>>>>>> 2: The range for schema:trailer includes MovieGameSeries >>>>>> >>>>>> https://github.com/schemaorg/schemaorg/issues/234 >>>>>> >>>>>>> 3: schema:musicBy has a much smaller domain than actor or >>>>>>> director >>>>>> >>>>>> https://github.com/schemaorg/schemaorg/issues/235 >>>>>> >>>>>>> 4: The range of foodEstablishment is FoodEstablishment or >>>>>>> Place; but: FoodEstablishment is a subclass of LocalBusiness >>>>>>> LocalBusiness is a subclass of Place, >>>>>> >>>>>> On this one I'm more sympathetic to Martin Hepp's point. Many >>>>>> local businesses have foody aspects to them but it isn't always >>>>>> feasible to make that explicit. However I'm wary of slipping into >>>>>> using rangeIncludes and domainIncludes assertions purely as a UI >>>>>> configuration language for the Web site. >>>>>> >>>>>>> Lots, lots more. >>>>>> >>>>>> Feel free to fwd or bug-file the entire horror! >>>>>> >>>>>> We have some very basic unit tests expressed in SPARQL - >>>>>> >>>>> https://github.com/schemaorg/schemaorg/blob/master/tests/test_graphs.py#L97 >>>>> >>>>> >>>>> > etc. which ought to catch more of these (e.g. mentions of types that >>>>>> don't have definitions should help avoid types). This currently >>>>>> requires Python RDFLib for the SPARQL tests, and I have had no >>>>>> success making SPARQL 1.1 property paths work as advertised, >>>>>> which I hoped might allow some basic matching against hierarchy. >>>>>> >>>>>> cheers, >>>>>> >>>>>> Dan >>>>>> >>>>>>> + The number of children (and adults) for which a Lodging >>>>> reservations can be made can be a floating point number. >>>>>> https://github.com/schemaorg/schemaorg/issues/232 >>>>>> >>>>> >>> >> > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1 > > iQEcBAEBAgAGBQJUwMTlAAoJECjN6+QThfjz67wIAKakbdg47aa74CSg5On12qrR > qqtcOZ3d+33aFjIg22ds+TelkzGGImqlj7mqmVwJQIBVF7QlWT2qSv/Nk97XbpqQ > V/ms1mL4889okcsu3+JdGKJSPati/cd8C4rWPC2P1NDS2zKODkQ7HQTouMenxzdg > TxfMQ3SjlsCrI5JVdt/jBFxkNSTksyIyWHElvf1rE5v51ERKOKLgxKLsOLQOFxWU > qETQS4s4GNqpGhGim6Ps/RWAVk1Sy5gEtTMB7HuJKkOO/tinK/2d5/4G0I3ytUOX > XgHb0o+rw59cHNJgr6IMug99fhmPTcykjzXWQRVxrtX3JFCnbW27lnOHutUgTmY= > =i6Sg > -----END PGP SIGNATURE----- >
Received on Thursday, 22 January 2015 10:30:52 UTC