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How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

Minimax learning lower bounds and optimal rates — Examples

1 · Prerequisites

2 · Logical flowchart

3 · Definitions, theorems and proofs

None yet.

4 · Examples, counterexamples and false statements

ExampleConstruction: AI-generatedVerification: AI-generatedjudge pass (gpt-6-luna)Open item page →

One-sample Bernoulli two-point testing

Example

Take u=1/2 and one observation, so P−=Bern⁡(1/4) and P+=Bern⁡(3/4). The deterministic test ψ(y)=y has equal-prior error 1/4, and this error is minimal among all randomized tests.

Facts & Assumptions

Given: The two laws P− and P+ on {0,1}, equal prior probabilities, and the test convention that ψ(y) is the probability of deciding +.

[F1]

The equal-prior average error ek(ψ) is the half-sum of the two conditional error probabilities A Bernoulli two-point testing lower bound.

Verification

1.1givenalgebra

Here P−(0)=3/4, P−(1)=1/4, P+(0)=1/4, and P+(1)=3/4. The test ψ(y)=y has error 12(P−(1)+P+(0))=14.

2.1givenF1algebra∎

For any randomized test ψ, direct expansion gives e1(ψ)=12+14(ψ(0)−ψ(1))≥14, since ψ(0)≥0 and ψ(1)≤1. The deterministic test attains this lower bound.

ExampleConstruction: AI-generatedVerification: AI-generatedjudge pass (gpt-6-luna)Open item page →

A finite class shattering three points

Example

Let X={x1,x2,x3} have the discrete sigma-algebra, and let H be the class of all eight functions from X to {0,1}. Then VCdim⁡(H)=3.

Facts & Assumptions

Given: The finite measurable space X and the class H={0,1}X.

[F1]

A class shatters an indexed finite set exactly when its trace family contains every subset of the index set; its VC dimension is the supremum of shattered cardinalities (Binary learning minimax excess risk, Shattering and the Vapnik–Chervonenkis dimension of a set family).

Verification

1.1givenF1construct

For each A⊆[3], the function hA defined by hA(xi)=1 exactly when i∈A belongs to H; hence the indexed trace family on {x1,x2,x3} is P([3]), so this set is shattered by [F1].

2.1givenF1algebra∎

The whole domain has only three points, so no subset of four distinct domain points exists. Thus no four-point set can be shattered, and the VC dimension is exactly three.

ExampleConstruction: AI-generatedVerification: AI-generatedjudge pass (gpt-6-luna)Open item page →

Fixed-confidence lower bounds at dimension four

Example

Let H be any nonempty measurable binary class of VC dimension 4 and let m=64. For every learner, there is a realizable law and target with probability at least 1/100 that target risk exceeds 3/2048, and there is an agnostic law with probability at least 1/64 that class excess risk exceeds 1/5120. The two laws may differ.

Facts & Assumptions

Given: A binary class H with VCdim⁡(H)=4, an integer sample size m=64, and a learner A.

[F1]

For d≥2 and m≥⌈(d−1)/4⌉, the realizable lower-bound error threshold is (d−1)/(32m) with failure probability at least 1/100 (A realizable VC minimax lower bound).

[F2]

For d≥2 and m≥⌈64d/5⌉, the agnostic lower-bound threshold is d/(320m) with failure probability at least 1/64 (An agnostic VC minimax lower bound).

[F3]

The VC dimension is the supremum of the cardinalities of finite shattered point sets (Binary learning minimax excess risk).

Verification

1.1givenF1F3algebra

By [F3] the given class has d=4. Hence ⌈(4−1)/4⌉=1≤64 and (4−1)/(32⋅64)=3/2048, so [F1] gives the realizable assertion.

2.1givenF2algebra∎

Also ⌈64⋅4/5⌉=52≤64 and 4/(320⋅64)=1/5120, so [F2] gives the agnostic assertion. The theorems allow different hard laws, as stated.

Sources