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Add lean source and binary files (part 61)
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import Mathlib
import OAI.Computability.DirectedFeedback.Games.Game
import OAI.Computability.DirectedFeedback.Games.SelectedLikelihood
namespace OAI
namespace DFVSGames.Foundations.Repetition.CompletedSampling
open scoped BigOperators
open Games
noncomputable section
section DistributionIdentities
variable {A B C D : Type*} [Fintype A] [Fintype B] [Fintype C] [Fintype D]
theorem mixture_pushforward_base (μ : FiniteDistribution A) (f : A → B)
(K : B → FiniteDistribution C) :
(μ.pushforward f).mixture K = μ.mixture (fun a => K (f a)) := by
apply FiniteDistribution.eq_of_weight_eq
intro c
exact FiniteDistribution.expectation_pushforward μ f (fun b => (K b).weight c)
theorem product_pushforward_eq_mixture_right (μ : FiniteDistribution A)
(ν : FiniteDistribution B) (f : A × B → C) :
(μ.product ν).pushforward f =
ν.mixture (fun b => μ.pushforward (fun a => f (a, b))) := by
classical
apply FiniteDistribution.eq_of_weight_eq
intro c
simp only [FiniteDistribution.pushforward, FiniteDistribution.product,
FiniteDistribution.mixture, Fintype.sum_prod_type]
rw [Finset.sum_comm]
apply Finset.sum_congr rfl
intro b _
rw [Finset.mul_sum]
apply Finset.sum_congr rfl
intro a _
by_cases h : f (a, b) = c <;> simp [h, mul_comm]
theorem product_product_pushforward_eq_mixture (μ : FiniteDistribution A)
(ν : FiniteDistribution B) (κ : FiniteDistribution C) (f : A → B → C → D) :
(μ.product (ν.product κ)).pushforward (fun z => f z.1 z.2.1 z.2.2) =
(μ.product ν).mixture
(fun z => κ.pushforward (fun c => f z.1 z.2 c)) := by
classical
apply FiniteDistribution.eq_of_weight_eq
intro d
simp only [FiniteDistribution.pushforward, FiniteDistribution.product,
FiniteDistribution.mixture, Fintype.sum_prod_type]
simp only [Finset.mul_sum, mul_ite, mul_zero, mul_assoc]
theorem mixture_totalVariation_le (μ ν : FiniteDistribution A)
(K : A → FiniteDistribution B) :
(μ.mixture K).totalVariation (ν.mixture K) ≤ μ.totalVariation ν := by
simpa only [FiniteDistribution.totalVariation, FiniteDistribution.mixture,
Information.totalVariation, kernelPushforward] using
totalVariation_kernelPushforward_le μ.weight ν.weight
(fun a => (K a).weight) (fun a => Information.gameLaw_isProbability (K a))
end DistributionIdentities
section Diagonal
variable {Z S : Type*} [Fintype Z] [Fintype S]
def diagonalLaw (σ : FiniteDistribution (Z × S)) : FiniteDistribution (Z × S × S) :=
Information.toGameLaw (diagonalWeights σ.weight)
(diagonalWeights_isProbability _ (Information.gameLaw_isProbability σ))
theorem diagonalLaw_eq_pushforward (σ : FiniteDistribution (Z × S)) :
diagonalLaw σ = σ.pushforward (fun z => (z.1, z.2, z.2)) := by
classical
apply FiniteDistribution.eq_of_weight_eq
rintro ⟨z, a, b⟩
change diagonalWeights σ.weight (z, a, b) =
(σ.pushforward (fun t => (t.1, t.2, t.2))).weight (z, a, b)
simp only [diagonalWeights, FiniteDistribution.pushforward,
Fintype.sum_prod_type, Prod.mk.injEq]
by_cases hab : a = b
· subst b
simp [ite_and]
· simp [hab, ite_and]
theorem diagonalLaw_mixture {T : Type*} [Fintype T]
(σ : FiniteDistribution (Z × S)) (K : Z × S × S → FiniteDistribution T) :
(diagonalLaw σ).mixture K = σ.mixture (fun z => K (z.1, z.2, z.2)) := by
rw [diagonalLaw_eq_pushforward, mixture_pushforward_base]
end Diagonal
section Completion
variable {X Y S Γ U V : Type*}
[Fintype X] [Fintype Y] [Fintype S] [Fintype Γ] [Fintype U] [Fintype V]
[DecidableEq X] [DecidableEq Y] [DecidableEq S]
abbrev Seed (Γ X Y S U V : Type*) :=
Γ × KernelSampling.Seed (X × S) (Y × S) U V
def seedLaw (γ : FiniteDistribution Γ)
(L : X × S → FiniteDistribution U) (R : Y × S → FiniteDistribution V) :
FiniteDistribution (Seed Γ X Y S U V) :=
γ.product (KernelSampling.seedLaw L R)
def left (sL : Γ → X → S) (seed : Seed Γ X Y S U V) (x : X) : U :=
KernelSampling.readLeft seed.2 (x, sL seed.1 x)
def right (sR : Γ → Y → S) (seed : Seed Γ X Y S U V) (y : Y) : V :=
KernelSampling.readRight seed.2 (y, sR seed.1 y)
def completionKernel (L : X × S → FiniteDistribution U)
(R : Y × S → FiniteDistribution V) (z : (X × Y) × S × S) :
FiniteDistribution (U × V) :=
(L (z.1.1, z.2.1)).product (R (z.1.2, z.2.2))
def outputLaw (μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution U) (R : Y × S → FiniteDistribution V) :
FiniteDistribution (U × V) :=
(seedLaw γ L R).mixture (fun seed =>
μ.pushforward (fun q => (left sL seed q.1, right sR seed q.2)))
theorem outputLaw_eq_product_pushforward
(μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution U) (R : Y × S → FiniteDistribution V) :
outputLaw μ γ sL sR L R =
(μ.product (seedLaw γ L R)).pushforward
(fun z => (left sL z.2 z.1.1, right sR z.2 z.1.2)) := by
exact (product_pushforward_eq_mixture_right μ (seedLaw γ L R)
(fun z : (X × Y) × Seed Γ X Y S U V =>
(left sL z.2 z.1.1, right sR z.2 z.1.2))).symm
theorem outputLaw_eq_mixture
(μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution U) (R : Y × S → FiniteDistribution V) :
outputLaw μ γ sL sR L R =
(sharedOutputLaw μ γ sL sR).mixture (completionKernel L R) := by
calc
outputLaw μ γ sL sR L R =
(μ.product γ).mixture (fun z =>
(KernelSampling.seedLaw L R).pushforward (fun table =>
(KernelSampling.readLeft table (z.1.1, sL z.2 z.1.1),
KernelSampling.readRight table (z.1.2, sR z.2 z.1.2)))) := by
rw [outputLaw_eq_product_pushforward]
exact product_product_pushforward_eq_mixture μ γ (KernelSampling.seedLaw L R)
(fun q seed table =>
(KernelSampling.readLeft table (q.1, sL seed q.1),
KernelSampling.readRight table (q.2, sR seed q.2)))
_ = (μ.product γ).mixture (fun z =>
completionKernel L R (z.1, sL z.2 z.1.1, sR z.2 z.1.2)) := by
apply congrArg ((μ.product γ).mixture)
funext z
exact KernelSampling.read_joint_pushforward L R
(z.1.1, sL z.2 z.1.1) (z.1.2, sR z.2 z.1.2)
_ = (sharedOutputLaw μ γ sL sR).mixture (completionKernel L R) := by
exact (mixture_pushforward_base (μ.product γ)
(fun z => (z.1, sL z.2 z.1.1, sR z.2 z.1.2)) (completionKernel L R)).symm
omit [DecidableEq X] [DecidableEq Y] [DecidableEq S] in
theorem diagonalLaw_completion_mixture
(σ : FiniteDistribution ((X × Y) × S))
(L : X × S → FiniteDistribution U) (R : Y × S → FiniteDistribution V) :
(diagonalLaw σ).mixture (completionKernel L R) =
σ.mixture (fun z => (L (z.1.1, z.2)).product (R (z.1.2, z.2))) := by
exact diagonalLaw_mixture σ (completionKernel L R)
theorem outputLaw_totalVariation_le
(μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution U) (R : Y × S → FiniteDistribution V)
(σ : FiniteDistribution ((X × Y) × S)) :
(outputLaw μ γ sL sR L R).totalVariation
(σ.mixture (fun z => (L (z.1.1, z.2)).product (R (z.1.2, z.2)))) ≤
(sharedOutputLaw μ γ sL sR).totalVariation (diagonalLaw σ) := by
rw [outputLaw_eq_mixture, ← diagonalLaw_completion_mixture σ L R]
exact mixture_totalVariation_le _ _ (completionKernel L R)
end Completion
variable {I X Y S Γ : Type*}
[Fintype I] [Fintype X] [Fintype Y] [Fintype S] [Fintype Γ]
[DecidableEq I] [DecidableEq X] [DecidableEq Y] [DecidableEq S]
def coordinateLeft (j : I) (sL : Γ → X → S)
(seed : Seed Γ X Y S (I → X) (I → Y)) (x : X) : I → X :=
KernelSampling.completedLeft j seed.2 (x, sL seed.1 x)
def coordinateRight (j : I) (sR : Γ → Y → S)
(seed : Seed Γ X Y S (I → X) (I → Y)) (y : Y) : I → Y :=
KernelSampling.completedRight j seed.2 (y, sR seed.1 y)
omit [Fintype I] [Fintype X] [Fintype Y] [Fintype S] [Fintype Γ]
[DecidableEq X] [DecidableEq Y] [DecidableEq S] in
@[simp] theorem coordinateLeft_preserves (j : I) (sL : Γ → X → S)
(seed : Seed Γ X Y S (I → X) (I → Y)) (x : X) :
coordinateLeft j sL seed x j = x := by
simp [coordinateLeft]
omit [Fintype I] [Fintype X] [Fintype Y] [Fintype S] [Fintype Γ]
[DecidableEq X] [DecidableEq Y] [DecidableEq S] in
@[simp] theorem coordinateRight_preserves (j : I) (sR : Γ → Y → S)
(seed : Seed Γ X Y S (I → X) (I → Y)) (y : Y) :
coordinateRight j sR seed y j = y := by
simp [coordinateRight]
def coordinateOutputLaw (μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(j : I) (sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution (I → X))
(R : Y × S → FiniteDistribution (I → Y)) :
FiniteDistribution ((I → X) × (I → Y)) :=
(seedLaw γ L R).mixture (fun seed => μ.pushforward
(fun q => (coordinateLeft j sL seed q.1, coordinateRight j sR seed q.2)))
theorem coordinateOutputLaw_eq_mixture
(μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(j : I) (sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution (I → X))
(R : Y × S → FiniteDistribution (I → Y))
(hL : ∀ q xs, (L q).weight xs ≠ 0 → xs j = q.1)
(hR : ∀ q ys, (R q).weight ys ≠ 0 → ys j = q.1) :
coordinateOutputLaw μ γ j sL sR L R =
(sharedOutputLaw μ γ sL sR).mixture (completionKernel L R) := by
calc
coordinateOutputLaw μ γ j sL sR L R =
(μ.product (seedLaw γ L R)).pushforward
(fun z => (coordinateLeft j sL z.2 z.1.1,
coordinateRight j sR z.2 z.1.2)) := by
exact (product_pushforward_eq_mixture_right μ (seedLaw γ L R)
(fun z : (X × Y) × Seed Γ X Y S (I → X) (I → Y) =>
(coordinateLeft j sL z.2 z.1.1, coordinateRight j sR z.2 z.1.2))).symm
_ = (μ.product γ).mixture (fun z =>
(KernelSampling.seedLaw L R).pushforward (fun table =>
(KernelSampling.completedLeft j table (z.1.1, sL z.2 z.1.1),
KernelSampling.completedRight j table (z.1.2, sR z.2 z.1.2)))) := by
exact product_product_pushforward_eq_mixture μ γ (KernelSampling.seedLaw L R)
(fun q seed table =>
(KernelSampling.completedLeft j table (q.1, sL seed q.1),
KernelSampling.completedRight j table (q.2, sR seed q.2)))
_ = (μ.product γ).mixture (fun z =>
completionKernel L R (z.1, sL z.2 z.1.1, sR z.2 z.1.2)) := by
apply congrArg ((μ.product γ).mixture)
funext z
exact KernelSampling.completed_joint_pushforward L R j hL hR
(z.1.1, sL z.2 z.1.1) (z.1.2, sR z.2 z.1.2)
_ = (sharedOutputLaw μ γ sL sR).mixture (completionKernel L R) := by
exact (mixture_pushforward_base (μ.product γ)
(fun z => (z.1, sL z.2 z.1.1, sR z.2 z.1.2)) (completionKernel L R)).symm
theorem coordinateOutputLaw_eq_outputLaw
(μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(j : I) (sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution (I → X))
(R : Y × S → FiniteDistribution (I → Y))
(hL : ∀ q xs, (L q).weight xs ≠ 0 → xs j = q.1)
(hR : ∀ q ys, (R q).weight ys ≠ 0 → ys j = q.1) :
coordinateOutputLaw μ γ j sL sR L R = outputLaw μ γ sL sR L R := by
rw [coordinateOutputLaw_eq_mixture μ γ j sL sR L R hL hR, outputLaw_eq_mixture]
theorem coordinateOutputLaw_totalVariation_le
(μ : FiniteDistribution (X × Y)) (γ : FiniteDistribution Γ)
(j : I) (sL : Γ → X → S) (sR : Γ → Y → S)
(L : X × S → FiniteDistribution (I → X))
(R : Y × S → FiniteDistribution (I → Y))
(hL : ∀ q xs, (L q).weight xs ≠ 0 → xs j = q.1)
(hR : ∀ q ys, (R q).weight ys ≠ 0 → ys j = q.1)
(σ : FiniteDistribution ((X × Y) × S)) :
(coordinateOutputLaw μ γ j sL sR L R).totalVariation
(σ.mixture (fun z => (L (z.1.1, z.2)).product (R (z.1.2, z.2)))) ≤
(sharedOutputLaw μ γ sL sR).totalVariation (diagonalLaw σ) := by
rw [coordinateOutputLaw_eq_outputLaw μ γ j sL sR L R hL hR]
exact outputLaw_totalVariation_le μ γ sL sR L R σ
end
end DFVSGames.Foundations.Repetition.CompletedSampling
namespace DFVSGames.Foundations.Games.Game
noncomputable section
variable {Q₁ Q₂ A₁ A₂ R₁ R₂ B₁ B₂ Seed : Type*}
[Fintype Q₁] [Fintype Q₂] [Fintype A₁] [Fintype A₂]
[Fintype R₁] [Fintype R₂] [Fintype B₁] [Fintype B₂] [Fintype Seed]
[Nonempty A₁] [Nonempty A₂]
def localEmbeddingLaw (G : Game Q₁ Q₂ A₁ A₂)
(seedLaw : FiniteDistribution Seed)
(left : Seed → Q₁ → R₁) (right : Seed → Q₂ → R₂) :
FiniteDistribution (R₁ × R₂) :=
seedLaw.mixture fun seed =>
G.questions.pushforward fun q => (left seed q.1, right seed q.2)
theorem success_le_value_add_embedding_distance
(G : Game Q₁ Q₂ A₁ A₂) (H : Game R₁ R₂ B₁ B₂)
(seedLaw : FiniteDistribution Seed)
(left : Seed → Q₁ → R₁) (right : Seed → Q₂ → R₂)
(answerLeft : Seed → Q₁ → B₁ → A₁)
(answerRight : Seed → Q₂ → B₂ → A₂)
(acceptance : ∀ seed x y a b,
H.accepts (left seed x) (right seed y) a b = true →
G.accepts x y (answerLeft seed x a) (answerRight seed y b) = true)
(strategy : Strategy R₁ R₂ B₁ B₂) :
H.success strategy ≤ G.value +
H.questions.totalVariation (G.localEmbeddingLaw seedLaw left right) := by
have localBound (seed : Seed) :
(G.questions.pushforward (fun q => (left seed q.1, right seed q.2))).probability
(H.wins strategy) ≤ G.value := by
let embedded : Game R₁ R₂ B₁ B₂ :=
{ questions := G.questions.pushforward fun q => (left seed q.1, right seed q.2)
accepts := H.accepts }
change embedded.success strategy ≤ G.value
exact (G.success_le_of_localSimulation embedded (left seed) (right seed)
(answerLeft seed) (answerRight seed) rfl (acceptance seed) strategy).trans
(G.success_le_value _)
have mixtureBound :
(G.localEmbeddingLaw seedLaw left right).probability (H.wins strategy) ≤ G.value :=
seedLaw.probability_mixture_le _ _ _ localBound
exact (H.questions.probability_le_add_totalVariation
(G.localEmbeddingLaw seedLaw left right) (H.wins strategy)).trans
(add_le_add mixtureBound (le_refl _))
def coordinateGame (G : Game Q₁ Q₂ A₁ A₂) {n : Nat} (coordinate : Fin n)
(law : FiniteDistribution ((Fin n → Q₁) × (Fin n → Q₂))) :
Game (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂) where
questions := law
accepts x y a b := G.accepts (x coordinate) (y coordinate) (a coordinate) (b coordinate)
theorem coordinate_probability_le_value_add_embedding_distance
(G : Game Q₁ Q₂ A₁ A₂) {n : Nat} (coordinate : Fin n)
(law : FiniteDistribution ((Fin n → Q₁) × (Fin n → Q₂)))
(seedLaw : FiniteDistribution Seed)
(left : Seed → Q₁ → Fin n → Q₁) (right : Seed → Q₂ → Fin n → Q₂)
(left_preserves : ∀ seed x, left seed x coordinate = x)
(right_preserves : ∀ seed y, right seed y coordinate = y)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂)) :
law.probability (G.coordinateWin strategy coordinate) ≤ G.value +
law.totalVariation (G.localEmbeddingLaw seedLaw left right) := by
apply G.success_le_value_add_embedding_distance (G.coordinateGame coordinate law)
seedLaw left right (fun _ _ a => a coordinate) (fun _ _ b => b coordinate)
intro seed x y a b h
simpa only [coordinateGame, left_preserves, right_preserves] using h
theorem coordinate_probability_le_value_of_approximate_embeddings
{SeedFamily : Nat → Type*} [∀ t, Fintype (SeedFamily t)]
(G : Game Q₁ Q₂ A₁ A₂) {n : Nat} (coordinate : Fin n)
(law : FiniteDistribution ((Fin n → Q₁) × (Fin n → Q₂)))
(seedLaw : (t : Nat) → FiniteDistribution (SeedFamily t))
(left : (t : Nat) → SeedFamily t → Q₁ → Fin n → Q₁)
(right : (t : Nat) → SeedFamily t → Q₂ → Fin n → Q₂)
(left_preserves : ∀ t seed x, left t seed x coordinate = x)
(right_preserves : ∀ t seed y, right t seed y coordinate = y)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
(distance : ℝ)
(close : ∀ η : ℝ, 0 < η → ∃ t,
law.totalVariation (G.localEmbeddingLaw (seedLaw t) (left t) (right t)) ≤
distance + η) :
law.probability (G.coordinateWin strategy coordinate) ≤ G.value + distance := by
by_contra h
have gap : 0 < law.probability (G.coordinateWin strategy coordinate) -
(G.value + distance) := sub_pos.mpr (lt_of_not_ge h)
obtain ⟨t, ht⟩ := close
((law.probability (G.coordinateWin strategy coordinate) - (G.value + distance)) / 2)
(by linarith)
have bound := G.coordinate_probability_le_value_add_embedding_distance coordinate law
(seedLaw t) (left t) (right t) (left_preserves t) (right_preserves t) strategy
linarith
end
end DFVSGames.Foundations.Games.Game
namespace DFVSGames.Foundations.Repetition
open scoped BigOperators
open Games CorrelatedSampling
noncomputable section
variable {Q₁ Q₂ A₁ A₂ S : Type*}
[Fintype Q₁] [Fintype Q₂] [Fintype A₁] [Fintype A₂] [Fintype S]
[Nonempty A₁] [Nonempty A₂] [Nonempty S]
[DecidableEq Q₁] [DecidableEq Q₂] [DecidableEq S] {n : Nat}
theorem coordinate_probability_le_value_of_local_completion
(G : Game Q₁ Q₂ A₁ A₂) (j : Fin n)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
(σ : FiniteDistribution ((Q₁ × Q₂) × S))
(profileL : Q₁ → FiniteDistribution S) (profileR : Q₂ → FiniteDistribution S)
(completionL : Q₁ × S → FiniteDistribution (Fin n → Q₁))
(completionR : Q₂ × S → FiniteDistribution (Fin n → Q₂))
(supportL : ∀ q xs, (completionL q).weight xs ≠ 0 → xs j = q.1)
(supportR : ∀ q ys, (completionR q).weight ys ≠ 0 → ys j = q.1)
(fallback : S) :
(σ.mixture (fun z => (completionL (z.1.1,z.2)).product
(completionR (z.1.2,z.2)))).probability (G.coordinateWin strategy j) ≤
G.value +
(2 * Information.totalVariation σ.weight
(fun z => G.questions.weight z.1 * (profileL z.1.1).weight z.2) +
2 * Information.totalVariation σ.weight
(fun z => G.questions.weight z.1 * (profileR z.1.2).weight z.2)) := by
let targetLaw := σ.mixture (fun z => (completionL (z.1.1,z.2)).product (completionR (z.1.2,z.2)))
let δ := 2 * Information.totalVariation σ.weight
(fun z => G.questions.weight z.1 * (profileL z.1.1).weight z.2) +
2 * Information.totalVariation σ.weight
(fun z => G.questions.weight z.1 * (profileR z.1.2).weight z.2)
change targetLaw.probability (G.coordinateWin strategy j) ≤ G.value + δ
by_contra h
have gap : 0 < targetLaw.probability (G.coordinateWin strategy j) - (G.value + δ) :=
sub_pos.mpr (lt_of_not_ge h)
let η := (targetLaw.probability (G.coordinateWin strategy j) - (G.value + δ)) / 2
have hη : 0 < η := by dsimp [η]; linarith
obtain ⟨N,hN⟩ := samplerOutputLaw_arbitrarily_close σ G.questions profileL profileR fallback η hη
let thresholds := sharedProfileThresholds profileL profileR
let γ := traceSeedLaw (rectangleDistribution (α := S) thresholds) N
let sL := samplerLocal thresholds profileL fallback N
let sR := samplerLocal thresholds profileR fallback N
have hvariation := CompletedSampling.coordinateOutputLaw_totalVariation_le
G.questions γ j sL sR completionL completionR supportL supportR σ
have hclose : (CompletedSampling.coordinateOutputLaw G.questions γ j sL sR completionL completionR).totalVariation targetLaw ≤ δ + η :=
hvariation.trans hN
have hsuccess := G.coordinate_probability_le_value_add_embedding_distance j targetLaw
(CompletedSampling.seedLaw γ completionL completionR)
(CompletedSampling.coordinateLeft j sL) (CompletedSampling.coordinateRight j sR)
(CompletedSampling.coordinateLeft_preserves j sL)
(CompletedSampling.coordinateRight_preserves j sR) strategy
have hsym : targetLaw.totalVariation
(G.localEmbeddingLaw (CompletedSampling.seedLaw γ completionL completionR)
(CompletedSampling.coordinateLeft j sL) (CompletedSampling.coordinateRight j sR)) =
(CompletedSampling.coordinateOutputLaw G.questions γ j sL sR completionL completionR).totalVariation targetLaw := by
unfold FiniteDistribution.totalVariation
congr 1
apply Finset.sum_congr rfl
intro q _
exact abs_sub_comm _ _
rw [hsym] at hsuccess
dsimp [η] at hclose
linarith
end
end DFVSGames.Foundations.Repetition
namespace DFVSGames.Foundations.Repetition
open scoped BigOperators
open Games
noncomputable section
variable {Q₁ Q₂ A₁ A₂ : Type*}
[Fintype Q₁] [Fintype Q₂] [Fintype A₁] [Fintype A₂]
[DecidableEq Q₁] [DecidableEq Q₂] {n : ℕ}
theorem selectedLabels_card (selected : Finset (Fin n)) :
Fintype.card (SelectedLabels (A₁ := A₁) (A₂ := A₂) selected) =
(Fintype.card A₁ * Fintype.card A₂) ^ selected.card := by
simp [SelectedLabels, Fintype.card_prod, mul_pow]
theorem unusedCoordinates_card (selected : Finset (Fin n)) :
Fintype.card {i : Fin n // i ∉ selected} = n - selected.card := by
classical
simp
theorem unusedCoordinates_card_real (selected : Finset (Fin n)) :
(Fintype.card {i : Fin n // i ∉ selected} : ℝ) = (n : ℝ) - selected.card := by
have hs : selected.card ≤ n := by simpa using Finset.card_le_univ selected
rw [unusedCoordinates_card, Nat.cast_sub hs]
theorem log_le_logTwo {x : ℝ} (hx : 1 ≤ x) : Real.log x ≤ logTwo x := by
have hlog : 0 ≤ Real.log x := Real.log_nonneg hx
have htwo : 0 < Real.log 2 := Real.log_pos (by norm_num)
have htwo_le : Real.log 2 ≤ 1 := by
convert Real.log_le_sub_one_of_pos (by norm_num : (0 : ℝ) < 2) using 1 ; norm_num
unfold logTwo
apply (le_div_iff₀ htwo).2
simpa using mul_le_mul_of_nonneg_left htwo_le hlog
theorem selectedLabels_log_le [Nonempty A₁] [Nonempty A₂]
(selected : Finset (Fin n)) (ell : ℝ)
(hell : logTwo ((Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ)) ≤ ell) :
Real.log (Fintype.card (SelectedLabels (A₁ := A₁) (A₂ := A₂) selected) : ℝ) ≤
(selected.card : ℝ) * ell := by
have ha : (1 : ℝ) ≤ Fintype.card A₁ := by exact_mod_cast Fintype.card_pos (α := A₁)
have hb : (1 : ℝ) ≤ Fintype.card A₂ := by exact_mod_cast Fintype.card_pos (α := A₂)
have hab : (1 : ℝ) ≤ (Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ) := by nlinarith
rw [selectedLabels_card, Nat.cast_pow, Nat.cast_mul, Real.log_pow]
exact mul_le_mul_of_nonneg_left ((log_le_logTwo hab).trans hell) (Nat.cast_nonneg _)
omit [DecidableEq Q₁] [DecidableEq Q₂] in
theorem selectedInformationRadius_le [Nonempty A₁] [Nonempty A₂]
(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)
(ell : ℝ)
(hell : logTwo ((Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ)) ≤ ell) :
selectedInformationRadius G strategy selected ≤
Real.sqrt (((n : ℝ) - selected.card) *
((selected.card : ℝ) * ell + logTwo (1 / G.selectedSuccess strategy selected))) := by
have hprob : 1 ≤ 1 / G.selectedSuccess strategy selected := by
apply (le_div_iff₀ positive).2
simpa using G.selectedSuccess_le_one strategy selected
have hbudget := add_le_add (selectedLabels_log_le (A₁ := A₁) (A₂ := A₂) selected ell hell)
(log_le_logTwo hprob)
unfold selectedInformationRadius
rw [← unusedCoordinates_card_real selected]
apply Real.sqrt_le_sqrt
exact mul_le_mul_of_nonneg_left hbudget (Nat.cast_nonneg _)
theorem sqrt_budget_factor (a b : ℝ) (ha : 0 < a) :
Real.sqrt (a * b) = a * Real.sqrt (b / a) := by
have he : a * b = a ^ 2 * (b / a) := by
field_simp
rw [he, Real.sqrt_mul (sq_nonneg a), Real.sqrt_sq (le_of_lt ha)]
omit [DecidableEq Q₁] [DecidableEq Q₂] in
theorem exists_coordinate_le_information_budget [Nonempty A₁] [Nonempty A₂]
(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)
(ell : ℝ)
(hell : logTwo ((Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ)) ≤ ell)
(hselected : selected.card < n)
(error : {i : Fin n // i ∉ selected} → ℝ)
(hsum : (∑ j, error j) ≤ 15 * selectedInformationRadius G strategy selected) :
∃ j : {i : Fin n // i ∉ selected}, error j ≤ 15 * Real.sqrt
(((selected.card : ℝ) * ell + logTwo (1 / G.selectedSuccess strategy selected)) /
((n : ℝ) - selected.card)) := by
classical
have hcard : 0 < Fintype.card {i : Fin n // i ∉ selected} := by
rw [unusedCoordinates_card]
exact Nat.sub_pos_of_lt hselected
let : Nonempty {i : Fin n // i ∉ selected} := Fintype.card_pos_iff.mp hcard
have hden : 0 < (n : ℝ) - selected.card := by
rw [← unusedCoordinates_card_real selected]
exact_mod_cast hcard
have htotal := hsum.trans (mul_le_mul_of_nonneg_left
(selectedInformationRadius_le G strategy selected positive ell hell) (by norm_num : (0 : ℝ) ≤ 15))
rw [sqrt_budget_factor _ _ hden] at htotal
have havg : (∑ j, error j) ≤ ∑ _j : {i : Fin n // i ∉ selected},
15 * Real.sqrt
(((selected.card : ℝ) * ell + logTwo (1 / G.selectedSuccess strategy selected)) /
((n : ℝ) - selected.card)) := by
simpa only [Finset.sum_const, Finset.card_univ, nsmul_eq_mul,
unusedCoordinates_card_real, mul_assoc, mul_left_comm] using htotal
obtain ⟨j, _, hj⟩ := Finset.exists_le_of_sum_le Finset.univ_nonempty havg
exact ⟨j, hj⟩
end
end DFVSGames.Foundations.Repetition
namespace DFVSGames.Foundations.Repetition.SelectionSequence
private theorem exists_unused_inline_SelectionSequence {n : Nat} (S : Finset (Fin n)) (hcard : S.card < n) :
∃ j : Fin n, j ∉ S := by
classical
apply Classical.byContradiction
intro h
have hall : ∀ j : Fin n, j ∈ S := by
intro j
apply Classical.byContradiction
intro hj
exact h ⟨j, hj⟩
have hfull : S = Finset.univ :=
Finset.ext (fun j => iff_of_true (hall j) (Finset.mem_univ j))
have hbad : n < n := by
simpa only [hfull, Finset.card_univ, Fintype.card_fin] using hcard
exact Nat.lt_irrefl n hbad
noncomputable def nextSet {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j)
(S : Finset (Fin n)) : Finset (Fin n) :=
if hs : S.card < n then insert (Classical.choose (witness S hs)) S else S
noncomputable def selectedSet {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j) : Nat → Finset (Fin n)
| 0 => ∅
| m + 1 => nextSet Step witness (selectedSet Step witness m)
theorem selectedSet_card {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j) (m : Nat) :
(selectedSet Step witness m).card = min m n := by
induction m with
| zero => simp [selectedSet]
| succ m ih =>
by_cases hm : m < n
· have hc : (selectedSet Step witness m).card = m := by
simpa only [Nat.min_eq_left (Nat.le_of_lt hm)] using ih
have hs : (selectedSet Step witness m).card < n := by
simpa only [hc] using hm
rw [selectedSet, nextSet, dite_eq_left hs,
Finset.card_insert_of_notMem ((Classical.choose_spec (witness _ hs)).1),
hc, Nat.min_eq_left (Nat.succ_le_of_lt hm)]
· have hc : (selectedSet Step witness m).card = n := by
simpa only [Nat.min_eq_right (Nat.le_of_not_gt hm)] using ih
have hs : ¬(selectedSet Step witness m).card < n := by
rw [hc]
exact Nat.not_lt.mpr (Nat.le_refl n)
rw [selectedSet, nextSet, dite_eq_right hs, hc,
Nat.min_eq_right (Nat.le_trans (Nat.le_of_not_gt hm) (Nat.le_succ m))]
theorem selectedSet_subset_succ {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j) (m : Nat) :
selectedSet Step witness m ⊆ selectedSet Step witness (m + 1) := by
change selectedSet Step witness m ⊆ nextSet Step witness (selectedSet Step witness m)
unfold nextSet
split
· exact Finset.subset_insert _ _
· exact le_rfl
theorem selectedSet_monotone {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j) :
Monotone (selectedSet Step witness) :=
monotone_nat_of_le_succ (selectedSet_subset_succ Step witness)
theorem selectedSet_univ {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j) :
selectedSet Step witness n = Finset.univ := by
apply Finset.eq_of_subset_of_card_le (Finset.subset_univ _)
simp [selectedSet_card]
theorem selectedSet_step {n : Nat}
(Step : Finset (Fin n) → Fin n → Prop)
(witness : ∀ S, S.card < n → ∃ j, j ∉ S ∧ Step S j)
(m : Nat) (hm : m < n) :
∃ j, j ∉ selectedSet Step witness m ∧
selectedSet Step witness (m + 1) = insert j (selectedSet Step witness m) ∧
Step (selectedSet Step witness m) j := by
have hc : (selectedSet Step witness m).card = m := by
rw [selectedSet_card, Nat.min_eq_left (Nat.le_of_lt hm)]
have hs : (selectedSet Step witness m).card < n := by simpa only [hc] using hm
let j := Classical.choose (witness (selectedSet Step witness m) hs)
have hj := Classical.choose_spec (witness (selectedSet Step witness m) hs)
refine ⟨j, hj.1, ?_, hj.2⟩
simp only [selectedSet, nextSet, dite_eq_left hs, j]
def SetStep {n : Nat} (P : Finset (Fin n) → ℝ) (v ell : ℝ)
(S : Finset (Fin n)) (j : Fin n) : Prop :=
P (insert j S) ≤ P S *
(v + 15 * Real.sqrt (((S.card : ℝ) * ell + logTwo (1 / P S)) /
((n : ℝ) - S.card)))
theorem totalSetStep {n : Nat} (P : Finset (Fin n) → ℝ) (v ell : ℝ)
(hnonneg : ∀ S, 0 ≤ P S) (hanti : Antitone P)
(hpositive : ∀ S, S.card < n → 0 < P S →
∃ j, j ∉ S ∧ SetStep P v ell S j) :
∀ S, S.card < n → ∃ j, j ∉ S ∧ SetStep P v ell S j := by
intro S hcard
by_cases hp : 0 < P S
· exact hpositive S hcard hp
· obtain ⟨j, hj⟩ := exists_unused_inline_SelectionSequence S hcard
have hz : P S = 0 := le_antisymm (le_of_not_gt hp) (hnonneg S)
have hnext : P (insert j S) = 0 := le_antisymm
((hanti (Finset.subset_insert j S)).trans (le_of_eq hz)) (hnonneg (insert j S))
refine ⟨j, hj, ?_⟩
simpa only [SetStep, hnext, hz, zero_mul] using (le_refl (0 : ℝ))
theorem exists_scalar_sequence {n : Nat} (P : Finset (Fin n) → ℝ) (v ell : ℝ)
(hempty : P ∅ = 1) (hnonneg : ∀ S, 0 ≤ P S) (hanti : Antitone P)
(hpositive : ∀ S, S.card < n → 0 < P S →
∃ j, j ∉ S ∧ SetStep P v ell S j) :
∃ p : Nat → ℝ, p 0 = 1 ∧ (∀ m, 0 ≤ p m) ∧ Antitone p ∧
ScalarRecurrence p n v ell ∧ p n = P Finset.univ := by
let witness := totalSetStep P v ell hnonneg hanti hpositive
let sets := selectedSet (SetStep P v ell) witness
let p := fun m => P (sets m)
refine ⟨p, ?_, ?_, ?_, ?_, ?_⟩
· change P (selectedSet (SetStep P v ell) witness 0) = 1
simpa only [selectedSet] using hempty
· intro m
exact hnonneg (sets m)
· intro i j hij
exact hanti (selectedSet_monotone (SetStep P v ell) witness hij)
· intro m hm
obtain ⟨j, _, hnext, hbound⟩ :=
selectedSet_step (SetStep P v ell) witness m hm
have hc : (selectedSet (SetStep P v ell) witness m).card = m := by
rw [selectedSet_card, Nat.min_eq_left (Nat.le_of_lt hm)]
change P (selectedSet (SetStep P v ell) witness (m + 1)) ≤ _
rw [hnext]
simpa only [SetStep, hc] using hbound
· change P (selectedSet (SetStep P v ell) witness n) = P Finset.univ
rw [selectedSet_univ]
open DFVSGames.Foundations.Games
variable {Q₁ Q₂ A₁ A₂ : Type*}
variable [Fintype Q₁] [Fintype Q₂] [Fintype A₁] [Fintype A₂]
variable [Nonempty A₁] [Nonempty A₂]
def ConditionalCoordinateBound (G : Game Q₁ Q₂ A₁ A₂) (n : Nat)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
(ell : ℝ) : Prop :=
∀ (S : Finset (Fin n)) (_hcard : S.card < n)
(hp : 0 < G.selectedSuccess strategy S),
∃ j, j ∉ S ∧
(((G.repetition n).questions.condition (G.selectedWins strategy S) hp).probability
(G.coordinateWin strategy j)) ≤
G.value + 15 * Real.sqrt
(((S.card : ℝ) * ell + logTwo (1 / G.selectedSuccess strategy S)) /
((n : ℝ) - S.card))
theorem repetition_success_le_of_conditionalCoordinateBound
(G : Game Q₁ Q₂ A₁ A₂) (n : Nat)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
{v ell : ℝ} (hvalue : G.value ≤ v) (hv1 : v < 1) (hell : 1 ≤ ell)
(hcoordinate : ConditionalCoordinateBound G n strategy ell) :
(G.repetition n).success strategy ≤
(1 - (1 - v)^3 / 6000)^((n : ℝ) / ell) := by
have hpositive : ∀ S : Finset (Fin n), S.card < n →
0 < G.selectedSuccess strategy S →
∃ j, j ∉ S ∧ SetStep (G.selectedSuccess strategy) v ell S j := by
intro S hcard hp
obtain ⟨j, hj, hbound⟩ := hcoordinate S hcard hp
refine ⟨j, hj, ?_⟩
change G.selectedSuccess strategy (insert j S) ≤ _
rw [G.selectedSuccess_insert strategy S j hp]
exact mul_le_mul_of_nonneg_left
(hbound.trans (add_le_add hvalue (le_refl _))) (le_of_lt hp)
obtain ⟨p, hp0, hpnonneg, hpmono, hrec, hpn⟩ :=
exists_scalar_sequence (G.selectedSuccess strategy) v ell
(G.selectedSuccess_empty strategy) (G.selectedSuccess_nonnegative strategy)
(G.selectedSuccess_antitone strategy) hpositive
have hbound := scalar_bound_6000 p n
(G.value_nonnegative.trans hvalue) hv1 hell hp0 hpnonneg hpmono hrec
rw [hpn, G.selectedSuccess_univ strategy] at hbound
exact hbound
end DFVSGames.Foundations.Repetition.SelectionSequence
namespace DFVSGames.Foundations.Repetition
open scoped BigOperators
open Games
noncomputable section
variable {Q₁ Q₂ A₁ A₂ : Type*}
[Fintype Q₁] [Fintype Q₂] [Fintype A₁] [Fintype A₂]
[Nonempty A₁] [Nonempty A₂]
[DecidableEq Q₁] [DecidableEq Q₂] {n : Nat}
theorem selected_coordinate_probability_le_value_add_error
(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}) :
((G.repetition n).questions.condition (G.selectedWins strategy selected) positive).probability
(G.coordinateWin strategy j.1) ≤
G.value + selectedEmbeddingError G strategy selected positive j := by
classical
let : Nonempty (SelectedCommonData (Q₁ := Q₁) (Q₂ := Q₂)
(A₁ := A₁) (A₂ := A₂) selected j) :=
finiteDistribution_nonempty (selectedProfileFallback G strategy selected positive j)
have h := coordinate_probability_le_value_of_local_completion G j.1 strategy
(selectedSamplingTarget G strategy selected positive j)
(selectedLeftProfile G strategy selected positive j)
(selectedRightProfile G strategy selected positive j)
(selectedFullLeftCompletion G strategy selected j)
(selectedFullRightCompletion G strategy selected j)
(selectedFullLeftCompletion_support G strategy selected j)
(selectedFullRightCompletion_support G strategy selected j)
(Classical.choice inferInstance)
have htarget : (selectedSamplingTarget G strategy selected positive j).mixture
(fun z => (selectedFullLeftCompletion G strategy selected j (z.1.1,z.2)).product
(selectedFullRightCompletion G strategy selected j (z.1.2,z.2))) =
(G.repetition n).questions.condition (G.selectedWins strategy selected) positive :=
selectedFullCompletionMixture_eq_conditionedQuestions G strategy selected positive j
rw [htarget, selectedSamplingTarget_left_error, selectedSamplingTarget_right_error] at h
exact h
theorem holenstein_conditionalCoordinateBound
(G : Game Q₁ Q₂ A₁ A₂) (n : Nat)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
(ell : ℝ)
(halphabet : logTwo ((Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ)) ≤ ell) :
SelectionSequence.ConditionalCoordinateBound G n strategy ell := by
intro selected hcard positive
obtain ⟨j,hj⟩ := exists_coordinate_le_information_budget G strategy selected positive ell
halphabet hcard (selectedEmbeddingError G strategy selected positive)
(selectedEmbeddingError_sum_le_fifteen G strategy selected positive)
exact ⟨j.1,j.property,
(selected_coordinate_probability_le_value_add_error G strategy selected positive j).trans
(add_le_add le_rfl hj)⟩
theorem holenstein_repetition_success
(G : Game Q₁ Q₂ A₁ A₂) (n : Nat)
(strategy : Strategy (Fin n → Q₁) (Fin n → Q₂) (Fin n → A₁) (Fin n → A₂))
{v ell : ℝ} (hvalue : G.value ≤ v) (hv : v < 1) (hell : 1 ≤ ell)
(halphabet : logTwo ((Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ)) ≤ ell) :
(G.repetition n).success strategy ≤
(1 - (1 - v)^3 / 6000)^((n : ℝ) / ell) :=
SelectionSequence.repetition_success_le_of_conditionalCoordinateBound G n strategy
hvalue hv hell (holenstein_conditionalCoordinateBound G n strategy ell halphabet)
theorem holenstein_repetition_value
(G : Game Q₁ Q₂ A₁ A₂) (n : Nat)
{v ell : ℝ} (hvalue : G.value ≤ v) (hv : v < 1) (hell : 1 ≤ ell)
(halphabet : logTwo ((Fintype.card A₁ : ℝ) * (Fintype.card A₂ : ℝ)) ≤ ell) :
(G.repetition n).value ≤
(1 - (1 - v)^3 / 6000)^((n : ℝ) / ell) := by
apply ((G.repetition n).value_le_iff _).2
intro strategy
exact holenstein_repetition_success G n strategy hvalue hv hell halphabet
end
end DFVSGames.Foundations.Repetition
end OAI