Re: Derived Attributes

Good stuff!

Any derived attribute that can be expressed as a mathematical formula (e.g.
over 21) could be exposed privately.
I think the "selective disclosure" body of work deals well with such
derived attributes.

On Wed, Aug 23, 2017 at 3:46 PM, David Chadwick <D.W.Chadwick@kent.ac.uk>
wrote:

>
>
> On 23/08/2017 13:19, Adam Sobieski wrote:
> > David,
> >
> > Thanks. I saw an attribute predicate in an animation (I thought is was a
> > derived attribute); I'm reading about attributes and predicates.
> >
> > For the example, it might make sense for an issuer to issue electoral
> > districts onto a credential, if we desire the capability for anonymous
> > feedback to elected officials and if the elected officials desire to
> > know that a feedback-provider is from an electoral district.
>
> Yes indeed. This would be a suitable credential for (in the UK case) a
> local authority to issue to a resident
>
> regards
>
> David
>
> >
> >
> > Best regards,
> > Adam
> >
> > *From:* David Chadwick <mailto:D.W.Chadwick@kent.ac.uk>
> > *Sent:* ‎Wednesday‎, ‎August‎ ‎23‎, ‎2017 ‎5‎:‎43‎ ‎AM
> > *To:* public-credentials@w3.org <mailto:public-credentials@w3.org>
> >
> > Hi Adam
> >
> > since credentials are signed by issuers, then I do not believe a
> > repository can implement a derived attribute, as a repository is not
> > usually a trusted issuer. I suggest the issuer will issue this if
> > requested to by the subject.
> >
> > regards
> >
> > David
> >
> > On 22/08/2017 21:51, Adam Sobieski wrote:
> >> Credentials Community Group,
> >>
> >> I would like to ask about /derived attributes/ (e.g. over 21 which is
> >> derived from birthdate and the current date), about how they are
> >> implemented by credential repositories towards understanding whether
> >> more complex derived attributes such as electoral districts might be
> >> possible.
> >>
> >> Electoral districts (https://en.wikipedia.org/wiki/Electoral_district)
> >> are dynamic regions. A digital wallet might inquire to a remote service
> >> about how an address or location maps to an electoral district (e.g.
> >> https://developers.google.com/civic-information/)
> >>
> >> Cities, states and electoral districts could be useful for government
> >> feedback forms, recording audio messages for or writing letters to
> >> Congresspeople via websites.
> >>
> >>
> >> Best regards,
> >> Adam Sobieski
> >
>
>