Unconditioned masses of surviving prefixes #
Completing a surviving initial word is first passage of the remaining forest. The exact mass is a product, and summing over the size gives the inclusive tail.
theorem
BGW.StableTrees.DiscreteForest.sizeEvent_prefixCylinder_mass
(μ : PMF ℕ)
(hc : IsCritical μ)
(hne : μ 1 ≠ 1)
{n m : ℕ}
{a : List ℕ}
(ham : a.length = m)
(hmn : m < n)
(hs : IsSurvivingPrefix a)
:
(LocallyFinite.bienaymeLaw μ.toMeasure) (LocallyFinite.sizeEvent n ∩ prefixCylinder m a) = (List.map (⇑μ) a).prod * forestWeight (⇑μ) (prefixStack a) (n - m)
The joint exact-size/prefix mass is the prefix weight times the remaining forest mass.
theorem
BGW.StableTrees.DiscreteForest.sizeEvent_prefixCylinder_real
(μ : PMF ℕ)
(hc : IsCritical μ)
(hne : μ 1 ≠ 1)
{n m : ℕ}
{a : List ℕ}
(ham : a.length = m)
(hmn : m < n)
(hs : IsSurvivingPrefix a)
:
(LocallyFinite.bienaymeLaw μ.toMeasure).real (LocallyFinite.sizeEvent n ∩ prefixCylinder m a) = degreeWeight μ a * forestMass μ (prefixStack a) (n - m)
The real-valued exact joint mass.
theorem
BGW.StableTrees.DiscreteForest.sizeGeEvent_prefixCylinder_real
(μ : PMF ℕ)
(hc : IsCritical μ)
(hne : μ 1 ≠ 1)
{n m : ℕ}
{a : List ℕ}
(ham : a.length = m)
(hmn : m < n)
(hs : IsSurvivingPrefix a)
:
(LocallyFinite.bienaymeLaw μ.toMeasure).real (Attraction.sizeGeEvent n ∩ prefixCylinder m a) = degreeWeight μ a * forestTail μ (prefixStack a) (n - m)
The real joint inclusive-tail/prefix mass.