Alphabeta Math
ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedprecheck passjudge 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.

Pairwise uncorrelated data can be jointly dependent

Example

Let Ω={(−1,−1,1),(−1,1,−1),(1,−1,−1),(1,1,1)} with each outcome assigned probability 1/4. Let X1,X2,X3 be the three coordinate random variables. This finite data vector is pairwise uncorrelated, but it is not mutually independent.

Facts & Assumptions

Given: The four-outcome uniform probability space Ω above and its three coordinate random variables.

[F1]

A finite probability space assigns nonnegative outcome weights summing to one; events are subsets of outcomes with probability the sum of their weights (Finite probability spaces, outcome weights, events, and event probabilities).

[F2]

A finite-valued real random variable is a function on the finite outcome space (Real random variables on finite probability spaces and their finite distributions).

[F3]

Expectation on a finite probability space is the weighted sum (Expectation of a real random variable on a finite probability space).

[F4]

Covariance is the expectation of the centered product (Variance, standard deviation, and covariance on a finite probability space).

[F5]

Mutual independence of finite-valued random variables requires factorization of every joint point probability (Pairwise and mutual independence of finite-valued random variables).

Verification

technique · enumerate the four outcomes
1.1F1F2F3givenalgebra

Each coordinate takes the value 1 twice and −1 twice. By [F1]–[F3], E[Xi]=0 and E[Xi2]=1 for each i∈{1,2,3}.

2.1F3F4step 1.1algebra

For each of the three pairs, the four products XiXj contain two 1 values and two −1 values. Thus E[XiXj]=0; using the means from step 1.1 in [F4] gives Cov⁡(Xi,Xj)=0 whenever i≠j.

3.1F1F5step 1.1algebra∎

The event {X1=1,X2=1,X3=1} contains only the outcome (1,1,1), so its probability is 1/4. Each event {Xi=1} has probability 1/2 by step 1.1. Mutual independence would give joint probability (1/2)3=1/8 by [F5], contradicting 1/4. Therefore the variables are not mutually independent.

Depends on

Used by

Nothing in the library uses this result yet.

Dependency tree · two levels

12 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.