700 likes | 807 Views
CMU Design Goals. { Kevin T. Kelly , Hanti Lin } Carnegie Mellon University. CMU. Responsive-ness. Qualitative Reasoning that Tracks Conditioning. Qualitative Reasoning that Tracks Conditioning. Qualitative Reasoning that Tracks Conditioning. Probabilistic conditioning.
E N D
CMU Design Goals { Kevin T. Kelly ,Hanti Lin } Carnegie Mellon University CMU Responsive-ness
Qualitative Reasoning that Tracks Conditioning Probabilistic conditioning
Qualitative Reasoning that Tracks Conditioning Probabilistic conditioning Acceptance
Qualitative Reasoning that Tracks Conditioning Probabilistic conditioning Acceptance Propositional belief revision
Qualitative Reasoning that Tracks Conditioning Probabilistic conditioning Acceptance Acceptance Propositional belief revision
Qualitative Reasoning that Tracks Conditioning Probabilistic conditioning Acceptance = Acceptance Propositional belief revision Conditioning + acceptance = acceptance + revision
Pre-established Harmony Probabilistic conditioning Propositional belief revision Acceptance
Cheap Bayes With Harmony Probabilistic conditioning Eat breakfast? Tie shoes? Get out of bed? Acceptance
When You Need Bayes… Help! Bayes! Probabilistic conditioning Invest? Eat breakfast? Tie shoes? Get out of bed? Acceptance
Call Him Then Condition only once Invest? Eat breakfast? Tie shoes? Get out of bed? Acceptance
Call Him Then Thanks. I’ll take it from here Condition only once Invest? TV? Eat breakfast? Tie shoes? Get out of bed? Acceptance
Expensive Bayes Without Harmony Invest? Repeated conditioning TV? Eat breakfast? Tie shoes? Get out of bed? Acceptance
Cheap Bayes with Harmony Condition only once Invest? TV? Eat breakfast? Tie shoes? Get out of bed? Acceptance
LMU Design Principle: Steadiness • Steadiness = “Just conjoin the new data with your old propositions if the two are consistent” LMU E B
AGM is Steady A B C
AGM is Steady A C
Non-steady Revision Rule • YoavShoham A B C
Non-steady Revision Rule • YoavShoham A C
Non-steady Revision Rule • YoavShoham A C
Some Shared Design Principles LMU CMU
Consistency Inconsistency is accepted nowhere.
Non-skepticism Every atom Ais accepted over some open neighborhood.
Non-Opinionation There is an open neighborhood over which you accept a non-atom and nothing stronger. • A v B
Corner-monotonicity If an atom is accepted, it continues to be accepted along the straight line to the corresponding corner. C
Corner-monotonicity If an atom is accepted, it continues to be accepted along the straight line to the corresponding corner. C C C C C
Sensible Rules Sensible = all four properties. • A v B C C C C C
Both are Sensible! CMU LMU A A A v C A v C A v B A v B T T B B C C B v C B v C
Incompatibility Theorem • No sensibleacceptance rule is both steadyand tracks conditioning. Sorry. You can’t have both. designer consumer
A New Paradox of Acceptance A p(.|A v B) A p A v B B C
A New Paradox of Acceptance A Accept A. Learn its consequenceA v B. If you track, you retractA! p(.|A v B) A p A v B B C
“Cautious” Monotonicity= Hypothetico-Deductive Monotonicity If you accept a hypothesis, don’t retract it when you learn what it entails(i.e. predicts).
A Better Idea? 0.9 A 0.8 A v C A v B T B C B v C
Another New Paradox of Acceptance A p p(.|B) B B
Another New Paradox of Acceptance A A p(.|B) p B
Another New Paradox of Acceptance A You will acceptA v Bno matterwhether B or B is learned. But if you track, you don’t accept A v B. A p(.|B) p T p(.|B) B B
Case Reasoning Accept a hypothesis, if you will accept it no matter whether E is learned or E is learned.
Theorem • The CMU rule + Shoham revision (non-steady) satisfies: • sensible • tracks conditioning • avoids both new paradoxes
Partial Converse • Shoham revision • sensible • tracks conditioning • Implies • CMU rule + avoidance of the 2 new paradoxes.
Gettier Without False Lemmas Nobody Gettier case Havit = the Truth Somebody Nogot
CMU Rule Represents it Nobody Havit = the Truth Somebody Nogot
CMU Rule is Unsteady! Nobody “Somebody” is retracted but not refuted. Havit Somebody Nogot
Gettier/Unsteadiness Zones Nobody Havit Somebody Nogot
Shoham Revision vs. AGM Revision Nobody Nogot Havit Nobody Nogot Havit
Shoham Revision vs. AGM Revision Nobody “Re-examine your reasons” Nogot Havit Nobody “Trust what you accepted” Nogot Havit
Structure Preservation Geometry Logic (0, 1, 0) Acpt (1/3, 1/3, 1/3) B A C (0, 0, 1) (1, 0, 0)
Some Clear Cases A B C
Interpolation A B C