OAI/NumberTheory/DukePrimeDegree/Entropy/CountableShannonInformation.lean

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6 declarations, 0 contain sorry, 0 declared as axioms

Integrable information for the countable return observations

The summable atom estimates for return refinements give the actual integrable information function, and bound every finite recoding.

  1. lemma OAI.DukePrimeDegree.integrableOn_observationInformation_fiber line 16
  2. lemma OAI.DukePrimeDegree.setIntegral_observationInformation_fiber line 25
  3. theorem OAI.DukePrimeDegree.countable_observationInformation_integrable line 40

    Source documentation

    Summable Shannon terms are sufficient for integrability of the countable partition's pointwise information.

    theorem countable_observationInformation_integrable
        {Y α : Type*} [MeasurableSpace Y] [Countable α]
        (μ : Measure Y) [IsProbabilityMeasure μ] (P : Y → α)
        (hP : ∀ a, MeasurableSet {y | P y=a})
        (hs : Summable (fun a => Real.negMulLog (μ.real {y | P y=a}))) :
        Integrable (observationInformation μ P) μ := by
    …

    Mentions: OAI.DukePrimeDegree.observationInformation

  4. theorem OAI.DukePrimeDegree.integral_countable_observationInformation line 57
  5. lemma OAI.DukePrimeDegree.ae_observation_fiber_pos line 75
  6. theorem OAI.DukePrimeDegree.finite_recode_entropy_le_countable_information line 88

    Source documentation

    Every finite recoding is bounded by the same countable Shannon sum.

    theorem finite_recode_entropy_le_countable_information
        {Y α β : Type*} [MeasurableSpace Y] [Countable α] [Fintype β]
        (μ : Measure Y) [IsProbabilityMeasure μ] (P : Y → α)
        (hP : ∀ a, MeasurableSet {y | P y=a})
        (hs : Summable (fun a => Real.negMulLog (μ.real {y | P y=a})))
        (f : α → β) (hf : ∀ b, MeasurableSet {y | f (P y)=b}) :
        observationEntropy μ (f ∘ P) ≤ ∑' a, Real.negMulLog (μ.real {y | P y=a}) := by
    …