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 data-dependent rule dominates a constant rule
Example
Let and observe with when and zero otherwise. Under squared-error loss, the constant rule has risk at and at . The data rule has risk zero at both parameters, so it dominates .
Facts & Assumptions
Given: The finite model, two decision rules, squared-error loss, and domination definition in the Example.
A probability measure has total mass one (Probability measures and probability spaces).
A statistic or estimator is a measurable data map (Statistics and estimators).
Risk is the expected loss under the sampling law (Loss functions and risk).
Domination requires weakly lower risk at every parameter and strict improvement at one parameter (Risk domination and admissibility).
Finite expectations are probability-weighted sums (Expectation agrees with the published finite weighted sum).
Verification
For each , let be the point mass at . In any disjoint sequence of events at most one event contains , so this law is countably additive and has total mass one; it is a probability measure by [F1]. Both maps and are measurable on the finite full-power-set spaces by [F2].
Under squared-error loss, the only data value with positive -mass is . The finite-sum formula [F5] and risk definition [F3] therefore give and .
The risks satisfy at both parameters, and the inequality is strict at . Thus dominates the constant rule by [F4].
Depends on
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
19 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.