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ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedjudge pass (gpt-6-luna)
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.

Correct ratios and a correct value model give separate DR identities

Example

Assume AC and take a one-step MDP with states s0,z, actions a,b at s0, action c at z, horizon H=1, and discount γ=12. Every action moves to z; action a gives reward 0, action b gives reward 1, and action c gives reward 0. The target policy chooses b at s0 and c at z, so its value from s0 is 1.

In the first evaluation case, behavior chooses a and b each with probability 12 at s0, the action ratios are exact, and the fitted Q values are Q^0(s0,a)=Q^0(s0,b)=Q^0(z,c)=0. The DR score is 2 on a logged b trajectory and 0 on a logged a trajectory, so its expectation is 1 although the Q model is wrong at b.

In the second evaluation case, behavior chooses a at s0 with probability 1, so the target action has no behavior support. The fitted model is exact: Q^0(s0,a)=0, Q^0(s0,b)=1, and Q^0(z,c)=0, with V^1=0 and V^0(s0)=1. Use the finite multipliers ρ^0(s0,a)=ρ^0(s0,b)=ρ^0(z,c)=1. Every behavior trajectory has zero residual, so its DR score is 1, equal to the target value despite missing support and incorrect action ratios.

In the diagram, vertices are states; an edge labeled a:r means action a produces reward r and moves deterministically to the arrow endpoint. The proof uses the transition/reward values stated in prose, not the drawing.

diagram failed to render:
\begin{tikzpicture}[>=stealth,thick]
\node[draw,circle] (s) at (0,0) {$s_0$};
\node[draw,circle] (z) at (3,0) {$z$};
\draw[->,bend left=18] (s) to node[above] {$a:0$} (z);
\draw[->,bend right=18] (s) to node[below] {$b:1$} (z);
\draw[->,loop right] (z) to node[right] {$c:0$} (z);
\end{tikzpicture}

Facts & Assumptions

Given: AC, the one-step MDP, both behavior policies, the target policy, the stated Q functions and multipliers, and H=1, γ=12.

[F1]

Finite-horizon offline reinforcement-learning dataset and coverage: the target value is the expected finite-horizon return, and behavior trajectories use the behavior policy with the same transition/reward law.

[F2]

Finite-horizon doubly robust off-policy value evaluation: with H=1, V1=0, the DR score is V^0(s0)+ρ^0(S0,A0)(R1−Q^0(S0,A0)).

[F3]

Doubly robust evaluation is unbiased under either exact component: exact ratios with trajectory coverage or a correct finite-horizon value model with the zero terminal convention suffices for unbiasedness.

Verification

1.1givenF1F2algebra

In the first case, V^0(s0)=12Q^0(s0,a)+12Q^0(s0,b)=0, ρ^0(s0,a)=0, and ρ^0(s0,b)=2. A logged a has score 0+0(0−0)=0; a logged b has score 0+2(1−0)=2. Since each occurs with probability 12, the mean DR score is 1, the target value, although Q^0(s0,b)=0≠1.

1.2givenF1F2F3algebra

In the second case, the exact finite-horizon model has Q0π(s0,a)=0, Q0π(s0,b)=1, and Q0π(z,c)=0; its target-policy value is V^0(s0)=1 and its terminal value is 0. The behavior policy always logs a, so each observed residual is 0+12⋅0−0=0, regardless of the supplied multiplier 1. Every DR score is therefore 1, and its expectation is the target value despite the absent target action in behavior data.

2.1step 1.1step 1.2F2F3algebra∎

The first calculation verifies the exact-ratio branch with a misspecified Q function; the second verifies the exact-model branch with missing support and incorrect multipliers. Both use the terminal convention V^1=0 from [F2].

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