Re: Finalizing Schema.org "Roles" design

On Thu, May 8, 2014 at 4:08 PM, Niklas Lindström <lindstream@gmail.com>wrote:

>
>
> On the other hand, it should be relatively easy for consumers of data to
>> translate such simple cases (an unconstrained role) to the direct pattern.
>
>
>> One thing I do not understand from the proposal is whether the additional
>> properties like startDate and endDate will be added to
>> http://schema.org/Role or whether the idea is that arbitrary local
>> property names can be used.
>>
>
> Is it the case that Role is always a form of temporal involvement, or
> participation, being a subclass of Event? Or is the design variable,
> (possibly) being conditioned somehow, but not always by time?
>

[Using Event in the Davidsonian sense rather than the schema:Event sense]

There are conflicting uses of the term "role" in ontologies, but don't
worry, there's also confusing overlaps with "actor". So that's ok.

Under one usage, roles relate an Event or Situation to things somehow
involved in the Event/Situation. If the things were directly involved, they
are often referred to as actors.

For example, there is a GettingInTheWayEvent E.  The getterInTheWay of E is
SimonsCat.  The gottenInTheWay of E is SimonsFiancee; these two individuals
were actors in the event.   Simon was not directly involved in E, but was a
maleficiary in it, due to having SimonsCat dumped on SimonsLap.  Simon
played a role in the event, but was not an actor.

In a slightly different context, roles are used instead of types for thinks
that are not always true about some individual.

For example, before moving to New York City,  Sheena enjoyed surfing and
disco music.  Subsequently she discovered the joys of Punk Rock, and
continues to follow the associated lifestyle.
Because Sheena was Sheena before *and* after this change, some schools of
thought* would hold that it is incorrect to say that Sheena *is a  *punk
rocker; rather, they would say that Sheena *is* playing the role of punk
rocker.

Both of these senses of role can involve beginnings and ends ; however, the
second usage is not a subtype of Event.

The second sense seems to better cover the Joe Montana example;  he played
the role of quarterback for the '49ers from '79-'92 (though not
continuously).  In '92 he stopped playing the role of quarterback for the
'49ers, and next season played the role of a quarterback for the Chiefs. He
continued to be Joe Montana.

You could say that there are temporal subParts of Joe Montana that are a
'49ers Quarterback.

An alternative would be to  say that in the time context of the years
'79-'92,  Joe Montana is a  Quarterback  for the '49ers.

Everyone can agree that he is the greatest QB of all time; all that remains
is how to say it.

Simon
*  but not  Rock 'n' Roll High Schools of thought