Re: PROV-ISSUE-411 (tracedto-inference): Should tracedTo allow tracing across specialization relation [prov-dm-constraints]

Graham, all

On 6/21/12 4:24 AM, Graham Klyne wrote:
> I think the slightly woolly description of tracedTo [1] makes it very hard to discuss what are reasonable inferences that involve 
> tracedTo.  For example, if an entity (E1) is created by an activity A1 associated with agent program (Ag1) that is also an entity 
> compiled by a compiler (E2) which was written by agent (Ag2).  Is it the case that that E1 tracedTo Ag2?  I think from the 
> description of tracedTo [1] and the rest that the answer is "Yes", but I could imagine different answers.
>
>   E1 <--genBy-- A1 --assocWith-> Ag1 <-genBy-- ?a <-used-- E2 --assocWith-> Ag2
>
I am not quite sure I can parse this example, but regardless, I think what follows is important:
> By comparison, my expectation is that specializationOf is quite clearly defined such that:
>
>   a specializationOf b
>
> would allow
>
>   P(b) |- P(a)
>
> for any provenance expression P.  This is based on "a shares all aspects of b". (cf. [2]).
I think this is precisely the sort of semantic statements we need to reason about the systems of rules and constraints that we are 
setting up -- which is otherwise quite arbitrary and ungrounded.

So aren't these semantic properties the ones we should be discussing?

-Paolo

Received on Thursday, 21 June 2012 19:02:11 UTC