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Add lean source and binary files (part 64)
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import Mathlib
import OAI.Computability.VertexCover.Repetition.SelectedMarginal
namespace OAI
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namespace UniqueGames.Foundations.Repetition
open scoped BigOperators
open Games Information
noncomputable section
theorem isProbability_comp_equiv {A B : Type*} [Fintype A] [Fintype B]
(e : A ≃ B) (p : B → ℝ) (hp : IsProbability p) :
IsProbability (fun a => p (e a)) := by
constructor
· intro a
exact hp.1 _
· rw [e.sum_comp]
exact hp.2
theorem partialRevealMarginal_isProbability
{I T X Y : Type*} [Fintype I] [DecidableEq I] [Fintype T]
[Fintype X] [Fintype Y] [DecidableEq X] [DecidableEq Y]
(μ : FiniteDistribution (X × Y)) (j : I)
(likelihood : T → (I → X × Y) → ℝ)
(hp : IsProbability (fullRevealMarginal μ j likelihood)) :
IsProbability (partialRevealMarginal μ j likelihood) := by
apply (maskedJoint_isProbability_iff _).mp
have h := isProbability_comp_equiv (revealSplitEquiv (T := T) j).symm _ hp
have he : (fun z => fullRevealMarginal μ j likelihood
((revealSplitEquiv (T := T) j).symm z)) =
maskedJoint (partialRevealMarginal μ j likelihood) := by
funext z
exact fullRevealMarginal_merge μ j likelihood z.1.1.1 z.1.1.2 z.1.2 z.2
rw [he] at h
exact h
variable {Q₁ Q₂ A₁ A₂ : Type*}
[Fintype Q₁] [Fintype Q₂] [Fintype A₁] [Fintype A₂]
[DecidableEq Q₁] [DecidableEq Q₂] {n : Nat}
abbrev SelectedCommonData (selected : Finset (Fin n))
(j : {i : Fin n // i ∉ selected}) :=
((selected → Q₁ × Q₂) × SelectedLabels (A₁ := A₁) (A₂ := A₂) selected) ×
({i : {i : Fin n // i ∉ selected} // i ≠ j} → Q₁ ⊕ Q₂)
theorem selected_fullReveal_isProbability (G : Game Q₁ Q₂ A₁ A₂)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
(selected : Finset (Fin n)) (positive : 0 < G.selectedSuccess strategy selected)
(j : {i : Fin n // i ∉ selected}) :
IsProbability (fullRevealMarginal G.questions j
(selectedOutsideLikelihood G strategy selected)) := by
have h := isProbability_comp_equiv
(selectedObservationEquiv (Q₁ := Q₁) (Q₂ := Q₂) (A₁ := A₁) (A₂ := A₂) selected).symm
_ (selectedRawMarginal_isProbability G strategy selected positive j)
have he : (fun z => selectedRawMarginal G strategy selected j
((selectedObservationEquiv (Q₁ := Q₁) (Q₂ := Q₂) (A₁ := A₁) (A₂ := A₂) selected).symm z)) =
fullRevealMarginal G.questions j (selectedOutsideLikelihood G strategy selected) := by
funext z
exact selectedRawMarginal_fullReveal G strategy selected j z
rw [he] at h
exact h
def selectedCommonLaw (G : Game Q₁ Q₂ A₁ A₂)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
(selected : Finset (Fin n)) (positive : 0 < G.selectedSuccess strategy selected)
(j : {i : Fin n // i ∉ selected}) :
FiniteDistribution (SelectedCommonData (Q₁ := Q₁) (Q₂ := Q₂)
(A₁ := A₁) (A₂ := A₂) selected j × (Q₁ × Q₂)) :=
toGameLaw (partialRevealMarginal G.questions j (selectedOutsideLikelihood G strategy selected))
(partialRevealMarginal_isProbability G.questions j _
(selected_fullReveal_isProbability G strategy selected positive j))
end
end UniqueGames.Foundations.Repetition
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end
end OAI