Characterizing normal forms for informational independence
Linda C. van der Gaag, J-J.Ch. Meyer · Utrecht University Repository (Utrecht University) · 1996
The concept of informational independence plays a k ey role in most knowledge-based systems.Although de ned dierently in dierent contexts, its basic properties have been axiomatised by J. Pearl and his co-researchers.Pearl's axiomatic system oers a set of inference rules for deriving new independence statements from an initial set of statements and as such allows for a normal form for representing independences.Pearl's axioms, however, focus on mutually disjoint sets of variables only.We show that focusing on disjoint sets of variables can hide various interesting properties of independence.We extend Pearl's axiomatic system to capture these properties and thereby i n troduce a new normal form for informational independence.