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 with each outcome assigned probability . Let 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 above and its three coordinate random variables.
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).
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).
Expectation on a finite probability space is the weighted sum (Expectation of a real random variable on a finite probability space).
Covariance is the expectation of the centered product (Variance, standard deviation, and covariance on a finite probability space).
Mutual independence of finite-valued random variables requires factorization of every joint point probability (Pairwise and mutual independence of finite-valued random variables).
Verification
Each coordinate takes the value twice and twice. By [F1]–[F3], and for each .
For each of the three pairs, the four products contain two values and two values. Thus ; using the means from step 1.1 in [F4] gives whenever .
The event contains only the outcome , so its probability is . Each event has probability by step 1.1. Mutual independence would give joint probability by [F5], contradicting . Therefore the variables are not mutually independent.
Depends on
- Finite probability spaces, outcome weights, events, and event probabilities
- Real random variables on finite probability spaces and their finite distributions
- Expectation of a real random variable on a finite probability space
- Variance, standard deviation, and covariance on a finite probability space
- Pairwise and mutual independence of finite-valued random variables
Used by
Nothing in the library uses this result yet.
Dependency tree · two levels
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