Stat.Concentration.Covering.Euclidean­Radial­Polynomial

This barrel exports finite-trace pseudo-dimension bounds and uniform polynomial L² covering certificates for compactly supported radial monomials with a moving finite-dimensional Euclidean center.

Geometry 12 core · 4 supporting This module defines compactly supported radial monomials with a moving center and proves finite-trace VC-subgraph bounds. ★ radialMonomialClass_hasPseudoDimAtMost

Euclidean radial monomials and their finite traces

This module defines compactly supported radial monomials with a moving center and proves finite-trace VC-subgraph bounds. The bounds are intentionally non-optimized. Their important features are that they depend only on the Euclidean dimension and the finite degree cutoff, and that they are stated at the trace level, without any assumption on an ambient probability measure.

Odd and even degrees are treated uniformly. On a nonnegative radial ray, every positive integral power is monotone, so a threshold on a radial power is again a distance threshold. Squared Euclidean distance then supplies the finite-dimensional affine lift used by the trace argument.

abbrev EuclideanPoint reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, the Euclidean point space is the real Euclidean space of that dimension.

Definition (Lean source)
d :
EuclideanPoint d :
Type
Causalean.Stat.Concentration.EuclideanRadialPolynomial.EuclideanPoint · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:25
abbrev RadiusPoint reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, the point-radius space is the set of pairs consisting of a point in the corresponding real Euclidean space and an arbitrary real radius threshold.

Definition (Lean source)
d :
RadiusPoint d :
Type
Causalean.Stat.Concentration.EuclideanRadialPolynomial.RadiusPoint · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:28
def movingCenterClosedBallClassifier reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a center point, and a point together with a radius threshold, the moving-center closed-ball classifier returns true exactly when the point lies at distance no greater than the threshold from the center.

Definition (Lean source)
d :
zr :
movingCenterClosedBallClassifier d x zr :
decide (dist zr.1 x ≤ zr.2)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.movingCenterClosedBallClassifier · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:34 · uses EuclideanPoint , RadiusPoint
def movingCenterBallExteriorClassifier reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a center point, and a point together with a radius threshold, the moving-center exterior classifier returns true exactly when the point lies at distance strictly greater than the threshold from the center.

Definition (Lean source)
d :
zr :
movingCenterBallExteriorClassifier d x zr :
decide (zr.2 < dist zr.1 x)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.movingCenterBallExteriorClassifier · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:39 · uses EuclideanPoint , RadiusPoint
abbrev ClosedBallParam reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, the closed-ball parameter space is the set of pairs consisting of a point in that real Euclidean space and a nonnegative real radius.

Definition (Lean source)
d :
ClosedBallParam d :
Type
Causalean.Stat.Concentration.EuclideanRadialPolynomial.ClosedBallParam · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:205
def euclideanClosedBallClassifier reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a closed-ball parameter, and a point in the corresponding Euclidean space, the closed-ball classifier returns true exactly when the point lies in the closed ball specified by that parameter.

Definition (Lean source)
d :
euclideanClosedBallClassifier d cr z :
decide (dist z cr.1 ≤ (cr.2 : ℝ))
Causalean.Stat.Concentration.EuclideanRadialPolynomial.euclideanClosedBallClassifier · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:211 · uses ClosedBallParam , EuclideanPoint
def radialAnnulusMonomial reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a bandwidth, two relative annulus endpoints, a natural-number degree, a center point, and an evaluation point, the radial annulus monomial equals (dist(z,x)/q)k(\operatorname{dist}(z,x)/q)^k when the distance from the evaluation point to the center lies between aqaq and bqbq, inclusive, and equals zero otherwise.

Definition (Lean source)
d :
q a b :
k :
x z :
radialAnnulusMonomial d q a b k x z :
if a * q ≤ dist z x ∧ dist z x ≤ b * q then (dist z x / q) ^ k else 0
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialAnnulusMonomial · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:277 · uses EuclideanPoint
abbrev RadialMonomialParam reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension and a maximal natural-number degree, the radial-monomial parameter space consists of a center in that Euclidean space paired with a degree from zero through pp.

Definition (Lean source)
d p :
RadialMonomialParam d p :
Type
EuclideanPoint d × Fin (p + 1)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.RadialMonomialParam · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:284
def radialMonomialClass reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a maximal degree, a bandwidth and two relative annulus endpoints, a center-and-degree parameter, and a Euclidean evaluation point, the radial-monomial class maps that parameter and point to the corresponding radial annulus monomial.

Definition (Lean source)
d p :
q a b :
radialMonomialClass d p q a b θ z :
radialAnnulusMonomial d q a b θ.2.1 θ.1 z
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialMonomialClass · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:291 · uses EuclideanPoint , RadialMonomialParam
def fixedRadialPseudoDimBound reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, the fixed-degree radial pseudo-dimension bound is the explicit Boolean-combination bound 23(d+3)+12^{3(d+3)+1}.

Definition (Lean source)
d :
fixedRadialPseudoDimBound d :
Causalean.Stat.Concentration.EuclideanRadialPolynomial.fixedRadialPseudoDimBound · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:296
def radialPseudoDimBound reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension and a maximal degree, the radial pseudo-dimension bound is the explicit finite-union bound 2(p+1)(23(d+3)+1+1)+12^{(p+1)(2^{3(d+3)+1}+1)+1} obtained by combining p+1p+1 fixed-degree bounds.

Definition (Lean source)
d p :
radialPseudoDimBound d p :
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialPseudoDimBound · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Geometry.lean:300
theorem radialMonomialClass_hasPseudoDimAtMost reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Pseudo-dimension bound for the moving-center radial-monomial class. For a positive bandwidth q, a nonnegative annulus inner radius a, and inner radius at most outer radius b, allowing both the Euclidean center and the monomial degree — ranging from zero through p — to vary gives the radial-monomial class a pseudo-dimension of at most radialPseudoDimBound d p.

Formal statement
d p :
q a b :
hq :
0 < q
ha :
0 ≤ a
hab :
a ≤ b
Proof (Lean source)
theorem radialMonomialClass_hasPseudoDimAtMost (d p : ℕ) {q a b : ℝ} (hq : 0 < q) (ha : 0 ≤ a) (hab : a ≤ b) : HasPseudoDimAtMost (radialMonomialClass d p q a b) (radialPseudoDimBound d p) := by let pi : (j : Fin (p + 1)) → EuclideanPoint d → (EuclideanPoint d × ℝ) → Bool := fun j => subgraphClassifier (fun x : EuclideanPoint d => radialAnnulusMonomial d q a b j.1 x) have hpi : ∀ j, HasVCAtMost (pi j) (fixedRadialPseudoDimBound d) := by intro j exact radialAnnulusMonomial_hasPseudoDimAtMost d j.1 hq ha hab have hu := finiteUnion_hasVCAtMost pi hpi have hr := HasVCAtMost.reindex hu (fun theta : RadialMonomialParam d p => (Sigma.mk theta.2 theta.1 : Sigma fun _ : Fin (p + 1) => EuclideanPoint d)) change HasVCAtMost (subgraphClassifier (radialMonomialClass d p q a b)) (radialPseudoDimBound d p) simp only [radialPseudoDimBound, Fintype.card_fin, pi, radialMonomialClass] at hr ⊢ exact hr
4 supporting declarations (lemmas, instances)
Cover 3 core · 14 supporting This module converts the finite-trace pseudo-dimension certificate into a uniform polynomial L²(Q) covering certificate. ★ radialMonomialOn_hasPolynomialL2Cover

Uniform polynomial covers for radial monomials

This module converts the finite-trace pseudo-dimension certificate into a uniform polynomial L²(Q) covering certificate. The measure Q remains arbitrary throughout, so atoms on moving annulus boundaries are included.

It also supplies two general assembly tools: pullback of a covering class along an arbitrary nonempty parameter map (using internal representatives at twice the preliminary radius), and the covering certificate for any bounded finite class. These tools let later score constructions reuse the existing sum and product closure lemmas.

def radialMonomialEnvelope reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

For an upper relative radius bb and a nonnegative integer pp, the radial-monomial envelope is (max{1,b})p(\max\{1,b\})^p.

Definition (Lean source)
b :
p :
radialMonomialEnvelope b p :
(max 1 b) ^ p
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialMonomialEnvelope · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Cover.lean:25
def radialMonomialOn reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given an observation space Ω\Omega, a Euclidean dimension dd, a maximum degree pp, a location map from observations to dd-dimensional Euclidean space, a bandwidth qq, annulus radii aa and bb, a radial-monomial parameter θ, and an observation ω\omega, the radial monomial evaluated at that observation is the corresponding radial-monomial class function evaluated at the mapped location.

Definition (Lean source)
Ω :
d p :
loc :
q a b :
ω :
Ω
radialMonomialOn d p loc q a b θ ω :
radialMonomialClass d p q a b θ (loc ω)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialMonomialOn · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Cover.lean:372 · uses EuclideanPoint , RadialMonomialParam
theorem radialMonomialOn_hasPolynomialL2Cover reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Covering certificate transported through a location map. For a measurable map from the underlying observation space into d-dimensional Euclidean space, given a positive bandwidth q, a nonnegative annulus inner radius a, and inner radius at most outer radius b, composing the moving-center radial-monomial class of degree at most p with the location map still carries a uniform polynomial covering certificate at envelope radialMonomialEnvelope b p.

Formal statement
Ω :
d p :
loc :
q a b :
hloc :
hq :
0 < q
ha :
0 ≤ a
hab :
a ≤ b
Proof (Lean source)
theorem radialMonomialOn_hasPolynomialL2Cover {Ω : Type u} [MeasurableSpace Ω] (d p : ℕ) (loc : Ω → EuclideanPoint d) {q a b : ℝ} (hloc : Measurable loc) (hq : 0 < q) (ha : 0 ≤ a) (hab : a ≤ b) : HasPolynomialL2Cover (radialMonomialOn d p loc q a b) (radialMonomialEnvelope b p) := by apply (HasPseudoDimAtMost.compDomain (radialMonomialClass_hasPseudoDimAtMost d p hq ha hab) loc).hasPolynomialL2Cover · intro θ exact (radialAnnulusMonomial_measurable d θ.2.1 q a b θ.1).comp hloc · unfold radialMonomialEnvelope positivity · intro θ ω apply abs_radialAnnulusMonomial_le d p θ.2.1 hq ha hab exact Nat.le_of_lt_succ θ.2.2
14 supporting declarations (lemmas, instances)
Score 8 core · 3 supporting This module assembles the moving-center radial basis into a bounded polynomial and then into the residual score shape used by local-polynomial empirical process arguments. ★ radialResidualScore_hasPolynomialL2Cover

Bounded radial-polynomial score classes

This module assembles the moving-center radial basis into a bounded polynomial and then into the residual score shape used by local-polynomial empirical process arguments. Coefficients range over the existing finite coefficient box, all polynomial terms share one moving center, and a finite signed arm may multiply the score.

The proofs are designed to reuse HasPolynomialL2Cover.add, .mul, .neg, .finSum, the bounded finite-class certificate, and parameter pullback. No measure regularity beyond measurability is imposed, so the result remains uniform for atomic probability measures.

def boundedRadialPolynomial reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a maximal degree, a bandwidth and two relative annulus endpoints, a coefficient bound, a center, a boxed coefficient vector, and an evaluation point, the bounded radial polynomial is the sum, over degrees zero through pp, of each coefficient times the corresponding radial annulus monomial about the shared center.

Definition (Lean source)
d p :
q a b B :
β :
CoeffBox (Fin (p + 1)) B
boundedRadialPolynomial d p q a b B x β z :
∑ k : Fin (p + 1), β.1 k * radialAnnulusMonomial d q a b k.1 x z
Causalean.Stat.Concentration.EuclideanRadialPolynomial.boundedRadialPolynomial · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:25 · uses CoeffBox , EuclideanPoint
abbrev RadialPolynomialParam reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a maximal degree, and a coefficient bound, the radial-polynomial parameter space consists of a Euclidean center paired with a coefficient vector whose every coordinate has absolute value at most BB.

Definition (Lean source)
d p :
B :
RadialPolynomialParam d p B :
Type
EuclideanPoint d × CoeffBox (Fin (p + 1)) B
Causalean.Stat.Concentration.EuclideanRadialPolynomial.RadialPolynomialParam · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:33
def boundedRadialPolynomialOn reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given an observation space equipped with a σ-algebra, a natural dimension, a maximal degree, a Euclidean location map, a bandwidth and two relative annulus endpoints, a coefficient bound, a radial-polynomial parameter, and an observation, the observation-indexed bounded radial polynomial is the bounded radial polynomial evaluated at the Euclidean location of that observation.

Definition (Lean source)
Ω :
d p :
loc :
q a b B :
ω :
Ω
boundedRadialPolynomialOn d p loc q a b B θ ω :
boundedRadialPolynomial d p q a b B θ.1 θ.2 (loc ω)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.boundedRadialPolynomialOn · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:40 · uses EuclideanPoint , RadialPolynomialParam
def radialPolynomialEnvelope reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given an outer relative radius, a maximal degree, and a coefficient bound, the radial-polynomial envelope is (p+1)B(p+1)B times the radial-monomial envelope at that outer radius and degree.

Definition (Lean source)
b :
p :
B :
radialPolynomialEnvelope b p B :
((p + 1 : ℕ) : ℝ) * B * radialMonomialEnvelope b p
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialPolynomialEnvelope · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:47
abbrev RadialResidualScoreParam reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a natural dimension, a maximal degree, a coefficient bound, and an arm index set, the radial residual-score parameter space consists of a radial-polynomial parameter paired with one arm index.

Definition (Lean source)
d p :
B :
A :
Type v
RadialResidualScoreParam d p B A :
Type (max 0 v)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.RadialResidualScoreParam · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:151
def radialResidualScore reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given an observation space equipped with a σ-algebra, an arm index set, a natural dimension, a maximal degree, a Euclidean location map, an arm-valued function, a response function, a bandwidth and two relative annulus endpoints, a coefficient bound, a degree index, a residual-score parameter, and an observation, the radial residual score is the product of the arm value, the selected radial annulus monomial, and the residual obtained by subtracting the shared-center boxed radial-polynomial fit from the response.

Definition (Lean source)
Ω :
A :
Type v
d p :
loc :
arm :
A → Ω → ℝ
response :
Ω → ℝ
q a b B :
j :
Fin (p + 1)
ω :
Ω
radialResidualScore d p loc arm response q a b B j θ ω :
arm θ.2 ω * radialAnnulusMonomial d q a b j.1 θ.1.1 (loc ω) * (response ω - boundedRadialPolynomial d p q a b B θ.1.1 θ.1.2 (loc ω))
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialResidualScore · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:159 · uses EuclideanPoint , RadialResidualScoreParam
def radialResidualScoreEnvelope reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given an outer relative radius, a maximal degree, a coefficient bound, and a response bound, the radial residual-score envelope is the radial-monomial envelope times the sum of RR and the radial-polynomial envelope.

Definition (Lean source)
b :
p :
B R :
radialResidualScoreEnvelope b p B R :
Causalean.Stat.Concentration.EuclideanRadialPolynomial.radialResidualScoreEnvelope · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Score.lean:171
theorem radialResidualScore_hasPolynomialL2Cover reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Covering certificate for a bounded finite-arm residual score. Given a measurable Euclidean location map, a finite family of arms, each measurable and bounded in absolute value by 1, a measurable response variable that is bounded in absolute value by R, together with a positive bandwidth q, a nonnegative annulus inner radius a, inner radius at most outer radius b, a positive polynomial-coefficient bound B, and a positive response bound R, then the score formed by multiplying a bounded arm function, a radial monomial, and the residual of the response against a boxed radial-polynomial fit carries a positive-envelope uniform polynomial L²(Q) covering certificate — with envelope radialResidualScoreEnvelope b p B R — over every probability measure Q, including atomic ones.

Formal statement
Ω :
A :
Type v
d p :
loc :
arm :
A → Ω → ℝ
response :
Ω → ℝ
q a b B R :
j :
Fin (p + 1)
hloc :
harmMeas :
∀ s, Measurable (arm s)
harmBound :
∀ s ω, |arm s ω| ≤ 1
hresponseMeas :
Measurable response
hresponseBound :
∀ ω, |response ω| ≤ R
hq :
0 < q
ha :
0 ≤ a
hab :
a ≤ b
hB :
0 < B
hR :
0 < R
HasPolynomialL2Cover (radialResidualScore d p loc arm response q a b B j) (radialResidualScoreEnvelope b p B R)
Proof (Lean source)
theorem radialResidualScore_hasPolynomialL2Cover {Ω : Type u} [MeasurableSpace Ω] {A : Type v} [Fintype A] (d p : ℕ) (loc : Ω → EuclideanPoint d) (arm : A → Ω → ℝ) (response : Ω → ℝ) {q a b B R : ℝ} (j : Fin (p + 1)) (hloc : Measurable loc) (harmMeas : ∀ s, Measurable (arm s)) (harmBound : ∀ s ω, |arm s ω| ≤ 1) (hresponseMeas : Measurable response) (hresponseBound : ∀ ω, |response ω| ≤ R) (hq : 0 < q) (ha : 0 ≤ a) (hab : a ≤ b) (hB : 0 < B) (hR : 0 < R) : HasPolynomialL2Cover (radialResidualScore d p loc arm response q a b B j) (radialResidualScoreEnvelope b p B R) := by classical let M := radialMonomialEnvelope b p let P := radialPolynomialEnvelope b p B have hM : 0 < M := by dsimp [M, radialMonomialEnvelope] positivity have hP : 0 < P := by dsimp [P, radialPolynomialEnvelope] have hp1 : (0 : ℝ) < (p + 1 : ℕ) := by positivity positivity have hU : 0 < M * (R + P) := by positivity cases isEmpty_or_nonempty A with | inl hA => letI : IsEmpty A := hA refine ⟨?_, ?_, ?_, ?_⟩ · simpa [radialResidualScoreEnvelope, M, P] using hU · intro θ exact isEmptyElim θ.2 · intro θ exact isEmptyElim θ.2 · refine ⟨1, 0, le_rfl, ?_⟩ intro Q hQ ε hε hε1 refine ⟨∅, ?_, ?_⟩ · simp · intro θ exact isEmptyElim θ.2 | inr hA => letI : Nonempty A := hA letI : Nonempty (CoeffBox (Fin (p + 1)) B) := ⟨⟨fun _ => 0, fun _ => by simpa using hB.le⟩⟩ have harm : HasPolynomialL2Cover arm 1 := finiteClass_hasPolynomialL2Cover arm (by norm_num) harmMeas harmBound have hleading : HasPolynomialL2Cover (fun x : EuclideanPoint d => fun ω => radialAnnulusMonomial d q a b j.1 x (loc ω)) M := by have hfull := radialMonomialOn_hasPolynomialL2Cover d p loc hloc hq ha hab have hpull := pullback hfull (fun x : EuclideanPoint d => (x, j)) exact hpull have hpoly := boundedRadialPolynomialOn_hasPolynomialL2Cover d p loc hloc hq ha hab hB have hresponse : HasPolynomialL2Cover (fun _ : Unit => response) R := by exact finiteClass_hasPolynomialL2Cover (fun _ : Unit => response) hR (fun _ => hresponseMeas) (fun _ => hresponseBound) have harmLeading := harm.mul hleading have hresidual := hresponse.add hpoly.neg have hsuper := harmLeading.mul hresidual have hpull := pullback hsuper (fun θ : RadialResidualScoreParam d p B A => ((θ.2, θ.1.1), ((), θ.1))) change HasPolynomialL2Cover (radialResidualScore d p loc arm response q a b B j) (M * (R + P)) simp only [one_mul] at hpull exact hpull
3 supporting declarations (lemmas, instances)
Trace 4 core · 6 supporting This module isolates the combinatorial tools used by the Euclidean radial construction. ★ booleanCombination_hasVCAtMost

Finite-trace tools for radial VC-subgraph classes

This module isolates the combinatorial tools used by the Euclidean radial construction. It gives a homogeneous linear-sign VC bound, deliberately coarse but explicit bounds for finite Boolean combinations and finite unions, and pullback lemmas for both Boolean VC dimension and pseudo-dimension.

The Boolean-combination theorem is trace-level: its combining formula may depend on the sampled point. This is important for radial subgraphs, where the formula changes according to the sign of the sampled threshold.

def booleanCombinationVCBound reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a number of Boolean component classes and a common VC-dimension bound, the Boolean-combination VC bound is the explicit natural number 2m(d+1)+12^{m(d+1)+1}.

Definition (Lean source)
m d :
booleanCombinationVCBound m d :
2 ^ (m * (d + 1) + 1)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.booleanCombinationVCBound · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:25
def finiteUnionVCBound reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a number of component classes and a common VC-dimension bound, the finite-union VC bound is the explicit natural number 2m(d+1)+12^{m(d+1)+1}.

Definition (Lean source)
m d :
finiteUnionVCBound m d :
2 ^ (m * (d + 1) + 1)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.finiteUnionVCBound · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:29
def linearSignClass reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

Given a finite feature index set, a real-valued feature family, a real coefficient vector, and an evaluation point, the homogeneous linear-sign classifier returns true exactly when the coefficient-feature inner product at that point is strictly positive.

Definition (Lean source)
𝒳 :
Type u
shared
K :
Type v
φ :
K → 𝒳 → ℝ
θ :
K → ℝ
x :
𝒳
linearSignClass φ θ x :
decide (0 < ∑ k, θ k * φ k x)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.linearSignClass · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:78
theorem booleanCombination_hasVCAtMost reviewed
Causalean.Stat.Concentration.EuclideanRadialPolynomial

VC bound for a point-dependent Boolean combination of classes. Given m independently parameterized Boolean classifier families, each of VC dimension at most d, applying to them any combining rule that may itself depend on the sampled point still yields a Boolean class of VC dimension at most booleanCombinationVCBound m d.

Formal statement
𝒳 :
Type u
shared
m d :
Fin m → Type v
π :
(j : Fin m) → ι j → 𝒳 → Bool
:
∀ j, HasVCAtMost (π j) d
combine :
𝒳 → (Fin m → Bool) → Bool
HasVCAtMost (fun θ : (j : Fin m) → ι j => fun x => combine x (fun j => π j (θ j) x)) (booleanCombinationVCBound m d)
Proof (Lean source)
theorem booleanCombination_hasVCAtMost {m d : ℕ} {ι : Fin m → Type v} (π : (j : Fin m) → ι j → 𝒳 → Bool) (hπ : ∀ j, HasVCAtMost (π j) d) (combine : 𝒳 → (Fin m → Bool) → Bool) : HasVCAtMost (fun θ : (j : Fin m) → ι j => fun x => combine x (fun j => π j (θ j) x)) (booleanCombinationVCBound m d) := by simpa only [booleanCombinationVCBound] using hasVCAtMost_of_growth_card_le (fun θ : (j : Fin m) → ι j => fun x => combine x (fun j => π j (θ j) x)) (m * (d + 1)) (fun n S => booleanCombination_growth_card_le (n := n) π hπ combine S)
Causalean.Stat.Concentration.EuclideanRadialPolynomial.booleanCombination_hasVCAtMost · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:423 · uses booleanCombinationVCBound , HasVCAtMost
6 supporting declarations (lemmas, instances)
  • reindex theorem — Reparameterizing a Boolean class by an arbitrary map cannot increase its finite-trace VC dimension.
    𝒳 :
    Type u
    shared
    ι :
    Type v
    κ :
    Type w
    π :
    ι → 𝒳 → Bool
    d :
    :
    e :
    κ → ι
    HasVCAtMost (fun k => π (e k)) d
    Proof (Lean source)
    theorem HasVCAtMost.reindex {ι : Type v} {κ : Type w} {π : ι → 𝒳 → Bool} {d : ℕ} (hπ : HasVCAtMost π d) (e : κ → ι) : HasVCAtMost (fun k => π (e k)) d := by intro n S apply (Finset.vcDim_mono (ℬ := growthFamily π S) ?_).trans (hπ n S) intro A hA rw [mem_growthFamily_iff] at hA ⊢ obtain ⟨k, rfl⟩ := hA exact ⟨e k, rfl⟩
    Causalean.Stat.Concentration.EuclideanRadialPolynomial.HasVCAtMost.reindex · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:33
  • compDomain theorem — Precomposing the observation argument of a Boolean class cannot increase its finite-trace VC dimension.
    𝒳 :
    Type u
    shared
    ι :
    Type v
    𝒴 :
    Type w
    π :
    ι → 𝒳 → Bool
    d :
    :
    g :
    𝒴 → 𝒳
    HasVCAtMost (fun i y => π i (g y)) d
    Proof (Lean source)
    theorem HasVCAtMost.compDomain {ι : Type v} {𝒴 : Type w} {π : ι → 𝒳 → Bool} {d : ℕ} (hπ : HasVCAtMost π d) (g : 𝒴 → 𝒳) : HasVCAtMost (fun i y => π i (g y)) d := by intro n S exact hπ n (fun j => g (S j))
    Causalean.Stat.Concentration.EuclideanRadialPolynomial.HasVCAtMost.compDomain · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:46
  • reindex theorem — Reparameterizing a real-valued class by an arbitrary map cannot increase its pseudo-dimension.
    𝒳 :
    Type u
    shared
    ι :
    Type v
    κ :
    Type w
    F :
    ι → 𝒳 → ℝ
    d :
    e :
    κ → ι
    HasPseudoDimAtMost (fun k => F (e k)) d
    Proof (Lean source)
    theorem HasPseudoDimAtMost.reindex {ι : Type v} {κ : Type w} {F : ι → 𝒳 → ℝ} {d : ℕ} (hF : HasPseudoDimAtMost F d) (e : κ → ι) : HasPseudoDimAtMost (fun k => F (e k)) d := by intro n T apply (Finset.vcDim_mono (ℬ := growthFamily (subgraphClassifier F) T) ?_).trans (hF n T) intro A hA rw [mem_growthFamily_iff] at hA ⊢ obtain ⟨k, rfl⟩ := hA exact ⟨e k, rfl⟩
    Causalean.Stat.Concentration.EuclideanRadialPolynomial.HasPseudoDimAtMost.reindex · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:55
  • compDomain theorem — Precomposing every function in a real-valued class with a fixed map cannot increase its pseudo-dimension.
    𝒳 :
    Type u
    shared
    ι :
    Type v
    𝒴 :
    Type w
    F :
    ι → 𝒳 → ℝ
    d :
    g :
    𝒴 → 𝒳
    HasPseudoDimAtMost (fun i y => F i (g y)) d
    Proof (Lean source)
    theorem HasPseudoDimAtMost.compDomain {ι : Type v} {𝒴 : Type w} {F : ι → 𝒳 → ℝ} {d : ℕ} (hF : HasPseudoDimAtMost F d) (g : 𝒴 → 𝒳) : HasPseudoDimAtMost (fun i y => F i (g y)) d := by intro n T exact hF n (fun j => (g (T j).1, (T j).2))
    Causalean.Stat.Concentration.EuclideanRadialPolynomial.HasPseudoDimAtMost.compDomain · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:69
  • linearSignClass_hasVCAtMost theorem — Homogeneous linear threshold classifiers in K real coordinates have VC dimension at most the number of coordinates.
    𝒳 :
    Type u
    shared
    K :
    Type v
    φ :
    K → 𝒳 → ℝ
    Proof (Lean source)
    theorem linearSignClass_hasVCAtMost {K : Type v} [Fintype K] (φ : K → 𝒳 → ℝ) : HasVCAtMost (linearSignClass φ) (card K) := by classical intro n S unfold vcDim refine Finset.sup_le fun s hs => ?_ rw [Finset.mem_shatterer] at hs by_contra hcard have hcard_lt : card K < s.card := by omega let v : {i // i ∈ s} → K → ℝ := fun i k => φ k (S i.1) have hvdep : ¬ LinearIndependent ℝ v := by intro hv have hle := hv.fintype_card_le_finrank rw [Module.finrank_pi, Fintype.card_coe] at hle omega obtain ⟨a, ha0, i0, hi0⟩ := Fintype.not_linearIndependent_iff.mp hvdep let g : {i // i ∈ s} → ℝ := if 0 < a i0 then a else fun i => -a i have hg0 : ∑ i, g i • v i = 0 := by dsimp [g] split_ifs · exact ha0 · calc ∑ i, (-a i) • v i = ∑ i, -(a i • v i) := by apply Finset.sum_congr rfl intro i _ exact neg_smul (a i) (v i) _ = -(∑ i, a i • v i) := by rw [Finset.sum_neg_distrib] _ = 0 := by rw [ha0, neg_zero] have hgi0 : 0 < g i0 := by dsimp [g] split_ifs with h · exact h · exact neg_pos.mpr (lt_of_le_of_ne (le_of_not_gt h) hi0) let g0 : Fin n → ℝ := fun i => if hi : i ∈ s then g ⟨i, hi⟩ else 0 let t : Finset (Fin n) := s.filter fun i => 0 < g0 i have hts : t ⊆ s := filter_subset _ _ obtain ⟨u, hu_growth, hsu⟩ := hs hts obtain ⟨θ, hθ⟩ := mem_growthFamily_iff.mp hu_growth have hlabel (i : {i // i ∈ s}) : linearSignClass φ θ (S i.1) = true ↔ 0 < g i := by rw [← restrictionPattern_mem_iff (p := linearSignClass φ θ) (S := S) (j := i.1), hθ] have hi_mem : i.1 ∈ u ↔ i.1 ∈ t := by constructor · intro hiu have : i.1 ∈ s ∩ u := Finset.mem_inter.mpr ⟨i.2, hiu⟩ rwa [hsu] at this · intro hit have : i.1 ∈ s ∩ u := by rwa [hsu] exact (Finset.mem_inter.mp this).2 rw [hi_mem] simp only [t, mem_filter, i.2, true_and] simp [g0, i.2] let e : {i // i ∈ s} → ℝ := fun i => ∑ k, θ k * φ k (S i.1) have he_pos (i : {i // i ∈ s}) (hi : 0 < g i) : 0 < e i := by simpa [linearSignClass, e] using (hlabel i).2 hi have he_nonpos (i : {i // i ∈ s}) (hi : ¬ 0 < g i) : e i ≤ 0 := by have hfalse : linearSignClass φ θ (S i.1) ≠ true := (hlabel i).not.mpr hi simpa [linearSignClass, e] using hfalse have hprod_nonneg (i : {i // i ∈ s}) : 0 ≤ g i * e i := by by_cases hi : 0 < g i · exact (mul_pos hi (he_pos i hi)).le · exact mul_nonneg_of_nonpos_of_nonpos (le_of_not_gt hi) (he_nonpos i hi) have hprod_pos : 0 < g i0 * e i0 := mul_pos hgi0 (he_pos i0 hgi0) have hsum_pos : 0 < ∑ i, g i * e i := Finset.sum_pos' (fun i _ => hprod_nonneg i) ⟨i0, Finset.mem_univ _, hprod_pos⟩ have hsum_zero : ∑ i, g i * e i = 0 := by have hcoord (k : K) : ∑ i, g i * v i k = 0 := by have := congrFun hg0 k simpa [Pi.smul_apply, smul_eq_mul] using this simp_rw [e, Finset.mul_sum] rw [Finset.sum_comm] apply Finset.sum_eq_zero intro k _ rw [show (∑ i, g i * (θ k * φ k (S i.1))) = θ k * ∑ i, g i * v i k by rw [Finset.mul_sum] apply Finset.sum_congr rfl intro i _ dsimp [v] ring] rw [hcoord, mul_zero] linarith
    Causalean.Stat.Concentration.EuclideanRadialPolynomial.linearSignClass_hasVCAtMost · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:83
  • finiteUnion_hasVCAtMost theorem — A finite union of m Boolean classes of VC dimension at most d has finite VC dimension bounded by finiteUnionVCBound m d.
    𝒳 :
    Type u
    shared
    K :
    Type v
    K → Type w
    d :
    π :
    (k : K) → ι k → 𝒳 → Bool
    :
    ∀ k, HasVCAtMost (π k) d
    HasVCAtMost (fun θ : Sigma ι => π θ.1 θ.2) (finiteUnionVCBound (card K) d)
    Proof (Lean source)
    theorem finiteUnion_hasVCAtMost {K : Type v} [Fintype K] {ι : K → Type w} {d : ℕ} (π : (k : K) → ι k → 𝒳 → Bool) (hπ : ∀ k, HasVCAtMost (π k) d) : HasVCAtMost (fun θ : Sigma ι => π θ.1 θ.2) (finiteUnionVCBound (card K) d) := by simpa only [finiteUnionVCBound] using hasVCAtMost_of_growth_card_le (fun θ : Sigma ι => π θ.1 θ.2) (card K * (d + 1)) (fun n S => finiteUnion_growth_card_le (n := n) π hπ S)
    Causalean.Stat.Concentration.EuclideanRadialPolynomial.finiteUnion_hasVCAtMost · Causalean/Stat/Concentration/Covering/EuclideanRadialPolynomial/Trace.lean:443