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Moments do not suffice to characterize Δ_n: extend beyond covariance and third moments

Prove that for every fixed integer k ≥ 1, there exist probability measures μ and ν on {0,1}^N that share all moments up to order k but have different asymptotic behaviors of the binomial empirical process, namely one with Δ_n(·) → 0 and the other with Δ_n(·) not → 0, thereby showing that knowledge of kth-order moments does not suffice to characterize the decay of Δ_n.

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Background

The authors construct two processes with identical pairwise covariances (and even identical third moments) but diverging behaviors of Δ_n(·): in one case Δ_n → 0, in the other Δ_n → 1/2. This disproves the hypothesis that covariance (or third-order moments) determine Δ_n’s convergence.

They conjecture that this phenomenon extends to any fixed moment order: for any k, matching moments up to order k still do not pin down whether Δ_n(μ) vanishes.

References

We conjecture that similar examples could be constructed to show that for any k≥q 1, knowledge of the kth order moments does not suffice to characterize the decay of Δn.

Correlated Binomial Process (2402.07058 - Blanchard et al., 10 Feb 2024) in After Theorem 2 (Covariance does not characterize Δ_n), Section 2 (Main results)