- From: Phil Barker <phil.barker@pjjk.co.uk>
- Date: Thu, 18 Jan 2018 11:42:04 +0000
- To: public-eocred-schema@w3.org
- Message-ID: <0db48425-a645-b647-094b-9b6dd37849b8@pjjk.co.uk>
Hello Fritz, I don't disagree with many of the points you raise, I think
you are (mostly) factually correct, but I do disagree with your
conclusion. This based on pragmatic judgement of what we can create and
maintain, what we can expect to be accepted as additions to schema.org,
and what we can expect providers of data to do.
additionalType is a possibility, worth discussing separately. My concern
is that it lacks support for text values. You and I both wish that more
data were provided as URIs, but the reality is that there are no URIs
for many of the credential subtypes. We have to support text values.
Adding subtypes of EducationalOccupationalCredential to schema.org for
all the specific types of credential is a non-starter for me. There
would be thousands. We couldn't hope to collect them all, and schema.org
would not accept so many.
Creating a typology along the lines of what is in CTDL, I also do not
think would work. I think 20 or so sub types would be too many for
schema. Doing anything meaningful by way of a global classification of
credential types is not a task I would want to take on (I've seen how
difficult it is just within Europe). Some examples of the difficulties
can be seen in trying to fit European credentials to CTDL. The
distinction between Diploma and Certificate in the UK's HND and HNC are
not well conveyed by the definitions for ceterms:Diploma and
ceterms:Certificate, and losing distinctions like this would be
detrimental to fulfilling the use case. I can also imagine all sorts of
errors in data provision arising from instances like the old-style
German Diplom and Spanish Licenciatura (comparable to Masters degrees,
not diploma or licence).
I do not agree that pointing to an externally defined term discourages
subtyping. If a DefinedTerm is part of a DefinedTermSet, relationships
between terms may be defined using vocabularies such as SKOS. However,
the harsh reality in which we have to operate is that they are more
likely to be defined in pdfs. Sorry.
Finally, remember the use case is to allow people to search for a
specific type of credential. For example, "where can I find information
about PGCEs?". credentialType="PGCE" would suffice in many cases.
Phil
On 17/01/18 18:07, Fritz Ray wrote:
> I want to say that Stuart and I have already had this discussion, but:
>
> I don't think credentialType is needed.
>
> Adding credentialType conflicts with the intent of the object's type.
> Remember, type is just a field as well.
>
> Schema.org/Thing also has http://schema.org/additionalType to permit
> the adding of additional (specific, not defined here) type data to any
> object.
>
> http://schema.org/Action is a good example of where a lot of subTypes
> are added to a base class without necessarily adding properties
> (though some do!), so we also have precident there.
>
> There's lots of established avenues that allow for subtyping. On the
> other hand, there are also several instances of additional type being
> specifically identified, usually paired with a fixed taxonomy of types
> (ActionStatusType, BoardingPolicyType, BusinessEntityType,
> EventStatusType). I also believe these instances aren't in the spirit
> of schema.org <http://schema.org>.
>
> Type properties like credentialType prevent additional subtyping and
> encourage "text" descriptions (see AlignmentObject's AlignmentType)
> where it should really be URLs so that interpretations can be
> distinguished and separate.
>
> Type properties also discourage additional subtyping and do not
> prevent a means of structuring dependent subtypes. Is an IVA
> credential (from the example above) a type of SVQ credential? Without
> an additional structured ontology to point at, it is difficult to know.
>
> What additional properties does a specific type of credential confer?
> For instance, a military MOS credential may have a
> securityClassificationLevel. Do we need to add those properties to the
> base class? (With credentialType, maybe, with subtypes, certainly not.)
>
> On Wed, Jan 17, 2018 at 9:04 AM, Stuart Sutton
> <stuartasutton@gmail.com <mailto:stuartasutton@gmail.com>> wrote:
>
> Phil, I agree that a credentialType property is needed. I think
> that having the range include both Text _and_ URL to allow
> identification by URI where available and text where not is
> appropriate. You are right that CTDL defines subclasses of it's
> Credential class <http://purl.org/ctdl/terms/Credential> and that
> no single enumeration will handle the breadth of the range (and
> internationalization issues); but, where such enumeration(s)
> exist, my sense is that they should be used. The CTDL defines a
> credentialType <http://purl.org/ctdl/terms/credentialType>
> property that is intended to be used wherever reference to a
> member of the Credential class is needed. It's range now
> enumerates the CTDL subclasses; but should likely reference more
> inclusively the Credential class.
>
> As for use of TermDefinition to identify/define members of such
> enumerations, I hope that it gets approved in a timely manner and
> that we are not forced to even contemplate use of AlignmentObject
> (ugh...don't get me started).
>
> Stuart
>
> On Wed, Jan 17, 2018 at 3:20 AM, Phil Barker
> <phil.barker@pjjk.co.uk <mailto:phil.barker@pjjk.co.uk>> wrote:
>
> Hello again, moving on to the next requirement for describing
> Educational and Occupational Credentials in schema.org
> <http://schema.org>: I suggest we look at how to identify the
> subtypes of these credentials.
>
> The use case for this
> <https://www.w3.org/community/eocred-schema/wiki/Use_Cases#Identify_subtypes_of_credential>
> gives examples of "degree" "certificate" "badge". I know there
> are about 20 others from the Credential Engines' CTDL
> <http://credreg.net/ctdl/handbook#creds>. Most countries will
> have their own types of EO Credential, for example in Scotland
> we have National Qualifications, HNDs, HNCs, SVQs, IVAs,
> PDAs, DipHEs, CertHEs and many more. Other countries will be
> similar. Furthermore, the types of qualification on offer
> changes over time.
>
> In short, the number of types is we need to consider is vast
> and varied. So, while CTDL has subclasses of its Credential
> class for each of its distinct types, that is not a practical
> solution for wider use. Even if we could reduce the number and
> variety of types, I think it would add too many subclasses to
> the schema.org <http://schema.org> hierarchy, given that most
> of the subtypes would have no unique properties.
>
> The alternative is for EducationalOccupationalCredential to
> have a property which records the type of credential. With a
> nod to Richard's point that much of what we do is applicable
> to generic credentials, I propose we call this credentialType.
>
> The basic range for credentialType would be text, and I think
> we should explicitly allow this. We could stop here.
>
> In an ideal world there would be controlled vocabulary for
> naming the credentialTypes. However, I a single controlled
> vocabulary of all the precise types is not feasible, and I
> think that producing a vocabulary that classifies these types
> into categories like "certificate" would be very difficult and
> the results would be very imprecise. We should, however try to
> facilitate the use of local controlled vocabularies. This is
> where we reach the edge of what currently possible in
> schema.org <http://schema.org>.
>
> Options for facilitating the use of local controlled
> vocabularies of credential type:
>
> 1, allow a URL to link to a controlled value / external
> enumeration.
>
> 2, allow alignmentObjects to provide information about the
> credentialType as if credential types were educational frameworks
>
> 3, use the developing schema.org <http://schema.org> type that
> is currently called CategoryCode
> <http://pending.schema.org/CategoryCode>, but which is
> proposed to be changed to TermDefinition
> <https://github.com/schemaorg/schemaorg/issues/1775>
>
> In my view: 1 is too vague (who knows what will be at the end
> of the URL), 2 stretches the alignmentObject somewhat, and 3
> is the best option for the long run. An example using option 3
> would look something like:
>
> {
> "@type": "EducationalOccupationalCredential",
> "name" : "HNC Facilities Management",
> "credentialType": {
> "@type" : "TermDefinition",
> "name" : "Higher National Certificate",
> "termCode" : "HNC",
> "inDefinedTermSet" : "SQA Qualifications" //should be a
> URL or DefinedTermSet object
> }
> }
>
> What do you think? Too complicated, maybe? Am I overthinking
> the problem? Are there enough well-constructed sets of terms
> describing credential types for it to be worth trying to
> accommodate anything other than text values?
>
> Phil
>
> --
>
> Phil Barker <http://people.pjjk.net/phil>.
> http://people.pjjk.net/phil
> PJJK Limited <https://www.pjjk.co.uk>: technology to enhance
> learning; information systems for education.
> CETIS LLP: a cooperative consultancy for innovation in
> education technology.
>
> PJJK Limited is registered in Scotland as a private limited
> company, number SC569282.
> CETIS is a co-operative limited liability partnership,
> registered in England number OC399090
>
>
>
>
> --
> Stuart A. Sutton, Metadata Consultant
> Associate Professor Emeritus, University of Washington
> Information School
> Email: stuartasutton@gmail.com <mailto:stuartasutton@gmail.com>
> Skype: sasutton
>
>
>
--
Phil Barker <http://people.pjjk.net/phil>. http://people.pjjk.net/phil
PJJK Limited <https://www.pjjk.co.uk>: technology to enhance learning;
information systems for education.
CETIS LLP: a cooperative consultancy for innovation in education technology.
PJJK Limited is registered in Scotland as a private limited company,
number SC569282.
CETIS is a co-operative limited liability partnership, registered in
England number OC399090
Received on Thursday, 18 January 2018 11:42:44 UTC