OAI/MeasureTheory/DyadicAvoidance/ExceptionalExpectation.lean

GitHub source file

2 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem310.Auxiliary.expected_density_eq_pointwise_probability line 15

    Source documentation

    For a finite random family of measurable sets, averaging their densities is identical to integrating pointwise membership probabilities.

    theorem expected_density_eq_pointwise_probability
        {Ω : Type u_Ω} [Fintype Ω] [MeasurableSpace Ω] [MeasurableSingletonClass Ω]
        (μ : Measure Ω) [IsProbabilityMeasure μ]
        (R : Ω → Set ℝ) (hR : ∀ ω, MeasurableSet (R ω)) :
        (∫⁻ ω, volume (R ω ∩ Icc (0 : ℝ) 1) ∂μ) =
          ∫⁻ x in Icc (0 : ℝ) 1, μ {ω | x ∈ R ω} := by
    …
  2. theorem OAI.Problem310.Auxiliary.expected_density_le_of_pointwise_bound line 36

    Source documentation

    A uniform bound outside a small exceptional set of centers controls the expected density. This is the integration step in the repair argument.

    theorem expected_density_le_of_pointwise_bound
        {Ω : Type u_Ω} [Fintype Ω] [MeasurableSpace Ω] [MeasurableSingletonClass Ω]
        (μ : Measure Ω) [IsProbabilityMeasure μ]
        (R : Ω → Set ℝ) (hR : ∀ ω, MeasurableSet (R ω))
        (G : Set ℝ) (hG : MeasurableSet G) (a : ENNReal)
        (hgood : ∀ x ∈ G, μ {ω | x ∈ R ω} ≤ a) :
        (∫⁻ ω, volume (R ω ∩ Icc (0 : ℝ) 1) ∂μ) ≤
          a + volume (Gᶜ ∩ Icc (0 : ℝ) 1) := by
    …