What legal inferences in OPM OPM Workshop Luc Moreau

A1A2P1 P2 used(R3) wasGene- ratedBy(R2) used(R1) wasTriggeredBy wasDerivedFrom Acc1 Acc3 Acc2 usedwasGeneratedBy wasDerivedFrom

Problem This rule leads to unexpected inferences

100g Flour 100g Sugar 2 eggs Bake bad Cake 100g Butter wasGeneratedBy(cake) used(flour) used(sugar) used(egg) used(butter) 1 egg wasGeneratedBy(unused)

Using this rule, we can infer that the – Unused egg was derived from the flour!

Origin of the Problem (1) Definition 5 [Artifact Used by Process]: In a graph, connecting a process to an artifact by a used edge is intended to indicate that the process required the availability of the artifact to complete its execution. When several artifacts are connected to a same process by multiple used edges, all of them were required for the process to complete.

Origin of the Problem (2) Definition 6 [Artifacts Generated by Processes] In a graph, connecting an artifact to a process by an edge wasGeneratedBy is intended to mean that the process was required to initiate its execution for the artifact to be generated. When several artifacts are connected to a same process by multiple wasGeneratedBy edges, the process had to have begun, for all of them to be generated.

Origin of the Problem (3) Inferring that an output was derived from a process input is therefore not valid

Solution to the Problem (1) PASOA model allows only one input per process and relationships are between 1 input and all the inputs that were required for the derivation to take place

Solution to the Problem (2) Rename wasDerivedFrom into mayHaveBeenDerivedFrom Very weak semantics

Solution to Problem (3) Strength definitions 5 – Definition 5: inputs need to be available for the process to begin (as opposed to complete)

Solution to Problem (4) Use time annotations to restricted permitted inferences Problem: we thought that provenance could be timeless Time is no longer really an annotation Causality implies time, but time does not imply causality!