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All PROV examples

  • author: Stian Soiland-Reyes

Identify the problem

After renaming of 'responsibility' to 'delegation' was agreed and implemented in PROV DM, the PROV-O qualified class prov:Responsibility was renamed to prov:Delegation.

This generalisation is generally good - but does implicitly change the direction of the qualified relationship as compared to prov:actedOnBehalfOf.

The PROV example

Turtle version:

Whiteboard version: DelegationSecretary.jpg

This example shows the delegation to give a secretary access to read emails. The unqualified relation is missing (marked as ?).

If you ask:

  • Who is the secretary that checks the email?
  • Which unqualified property should go for ? - and in which direction?

Then the graph above seems to indicate that Bob has delegated email checking to the agent Alice - hence Alice is the secretary.

However the upper ? is not the inverse prov:hadDelegate from Bob to Alice, but prov:actedOnBehalfOf from Bob to Alice - and it is in fact Bob who is the secretary.

The sources for confusions here are:

  • prov:agent hints at agency, that Alice is an agent for Bob
  • The direction of delegation is generally "Manager delegates to Office Droid", so the qualification pattern with prov:Delegation could read like "Bob delegated to Alice" - rather than "Alice was a delegate for Bob"

Potential solutions

  • Make prov:hadDelegate be the unqualified property and change the direction of prov:Delegation
    • Should then be pretty obvious; would not have prov:Agent problem
    • ..but wrong direction/term according to DM..
      • DM to change actedOnBehalfOf(responsible, delegate) to hadDelegate(delegate, responsible)?
  • Use more specific properties like prov:responsible rather than confusing prov:agent<code>
    • but.. harder to identify the 'special' outgoing link of qualification
  • Rename <code>prov:Delegation and prov:qualifiedDelegation
    • prov:Delegate
    • prov:ActedOnBehalfOf
    •  ?