OAI/NumberTheory/PrimePackets/ConditionalShannon.lean

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6 declarations, 0 contain sorry, 0 declared as axioms

Finite conditional entropy, including zero-mass cells

These algebraic chain rules are used to compare finite observations with the expanding leaf partitions in the metric entropy calculation.

  1. lemma OAI.PrimeDegreePackets.finiteShannon_mul line 17
  2. lemma OAI.PrimeDegreePackets.finiteShannon_mass_decomposition line 24
  3. theorem OAI.PrimeDegreePackets.finiteShannon_joint_mass_le line 47

    Source documentation

    Subadditivity for a nonnegative finite measure; its total mass need not be one.

    theorem finiteShannon_joint_mass_le {α β : Type*} [Fintype α] [Fintype β]
        (p : α × β → ℝ) (hp : ∀ z, 0 ≤ p z) :
        finiteShannon p + Real.negMulLog (∑ z, p z) ≤
          finiteShannon (fun a => ∑ b, p (a,b)) +
          finiteShannon (fun b => ∑ a, p (a,b)) := by
    …

    Mentions: OAI.PrimeDegreePackets.finiteShannon

  4. theorem OAI.PrimeDegreePackets.finiteShannon_submodular line 80

    Source documentation

    The finite entropy submodularity inequality H(ABC)+H(A) ≤ H(AB)+H(AC).

    theorem finiteShannon_submodular {α β γ : Type*}
        [Fintype α] [Fintype β] [Fintype γ]
        (p : α × (β × γ) → ℝ) (hp : ∀ z, 0 ≤ p z) :
        finiteShannon p + finiteShannon (fun a => ∑ z : β × γ, p (a,z)) ≤
          finiteShannon (fun z : α × β => ∑ c, p (z.1,(z.2,c))) +
          finiteShannon (fun z : α × γ => ∑ b, p (z.1,(b,z.2))) := by
    …

    Mentions: OAI.PrimeDegreePackets.finiteShannon

  5. lemma OAI.PrimeDegreePackets.finiteShannon_fst_le line 90
  6. lemma OAI.PrimeDegreePackets.finiteShannon_joint_decomposition line 97