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ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedprecheck pass
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.

A predictable linear forecast and its empirical residual process

Example

Assume AC, fix δ∈(0,1), and choose a Borel one-sided sub-exponential uniform boundary uδ/2,1 with crossing probability δ/2 at scale 1. Let X1,X2,… be independent Bernoulli random variables with success probability 1/4, set X0=0, and let F0={∅,Ω} and Ft=σ(X1,…,Xt). Use the predictable linear forecast X^t=1/4+(1/2)Xt−1. Then X^t∈[0,1] and E[Xt∣Ft−1]=1/4 almost surely. On the path (X1,X2,X3,X4)=(1,0,0,1), which has probability 9/256, the algorithm has Xˉ4=1/2, V4=7/4, and returns C4=[12−uδ/2,1(7/4)4,  12+uδ/2,1(7/4)4]. The forecast is predictable and differs from the conditional mean when Xt−1=1; the full interval sequence still covers its target sequence with probability at least 1−δ.

Facts & Assumptions

Given: Assume AC. The Bernoulli stream, filtration, forecast, error level, boundary, algorithm, and target sequence in the Example.

[F1]

Conditional expectation given a sigma algebra: a conditional-expectation version is measurable and has the defining event integrals.

[F2]

Conditional expectation is unique almost surely: conditional-expectation versions with the same input and conditioning sigma-algebra agree almost surely.

[F3]

Empirical-Bernstein confidence-sequence interval update: at time t, the output is centered at Xˉt with radius uδ/2,1(Vt)/t.

[F4]

Empirical-Bernstein confidence sequence under adaptive sampling: for these bounded observations and predictable forecasts, the intervals cover the running average conditional-mean target at all times with probability at least 1−δ.

[A1]

The Axiom of Choice: AC is explicitly assumed here and by the coverage theorem; the definition of a conditional-expectation version imposes no AC assumption.

Verification

1.1givenF1F2

For each t, the atoms of Ft−1 are the events Ax={(X1,…,Xt−1)=x}, with A=Ω for t=1. Each atom has positive probability, and independence gives P(Xt=1,Ax)=14P(Ax) and P(Xt=0,Ax)=34P(Ax). Thus the constant 1/4 has the defining event integrals on every atom and every union of atoms, so it is a version of E[Xt∣Ft−1] by [F1]; [F2] identifies it with the chosen conditional-expectation class.

2.1givenstep 1.1algebra

The forecast X^t is a function of Xt−1, hence Ft−1-measurable, and its values are 1/4 or 3/4; when Xt−1=1 it equals 3/4, not the conditional mean 1/4. On the specified path, the four squared errors are 9/16,9/16,1/16,9/16, so V4=28/16=7/4 and Xˉ4=2/4=1/2. Independence gives the path probability (1/4)(3/4)(3/4)(1/4)=9/256.

3.1givenF3F4A1step 1.1algebra∎

By [F3], the algorithm returns the displayed interval at time 4. Its hypotheses hold with a=0, b=1; therefore [F4] gives P(μt∈Ct for every t≥1)≥1−δ. In particular, using [A1], the interval sequence is a confidence sequence for the adapted target process defined in the Example.

Depends on

Used by

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