Stopped band-count errors #
The sandwich uses partial sums at both H and H+1. Doubling the cutoff reserves
the extra cycle; the ceiling contribution is negligible at each fixed positive band.
theorem
BGW.StableTrees.DiscreteHeightApprox.bandCount_error_le
{ω : ℕ → ℕ}
(hω : EpochsFinite ω)
(k : ℕ)
{a r : ℝ}
(ha : 0 < a)
(hlo : |∑ i ∈ Finset.range (weakLadderCount ω k), ↑(clusterVisits ω a i) - ↑(weakLadderCount ω k) * ↑⌈a⌉₊| ≤ r)
(hhi : |∑ i ∈ Finset.range (weakLadderCount ω k + 1), ↑(clusterVisits ω a i) - ↑(weakLadderCount ω k + 1) * ↑⌈a⌉₊| ≤ r)
:
A sandwich between the two adjacent cycle sums transfers a uniform centered-sum bound.
theorem
BGW.StableTrees.DiscreteHeightApprox.stopped_bandCount_error
{μ : PMF ℕ}
{θ : ℝ}
{B : ℕ → ℝ}
(h : StableDomain μ θ B)
(t : NNReal)
{x δ : ℝ}
(hx : 0 < x)
(hδ : 0 < δ)
:
Filter.Tendsto
(fun (ε : ℝ) =>
Filter.limsup
(fun (n : ℕ) =>
↑(DiscreteForest.offspringSeqLaw μ)
{ω : ℕ → ℕ | ↑(weakLadderCount ω ⌊↑n * ↑t⌋₊) ≤ x * ↑n / B n ∧ δ * (↑n * ε) < |↑(bandCount ω ⌊↑n * ↑t⌋₊ (ε * B n)) - ↑⌈ε * B n⌉₊ * ↑(weakLadderCount ω ⌊↑n * ↑t⌋₊)|})
Filter.atTop)
(nhdsWithin 0 (Set.Ioi 0)) (nhds 0)
Stopped renewal error for the band count (cutoff event H_k ≤ x n/B_n, k = ⌊nt⌋):
bandCount ω k (ε B_n) ≈ ⌈ε B_n⌉ H_k up to δ n ε, two limits.