Documentation

Copula.Rank.Integration

← Copula mathematical handbook

Integration tools for population rank coefficients #

theorem ProbabilityTheory.Copula.integral_unitInterval (f : ℝ → ℝ) :
∫ (u : ↑unitInterval), f ↑u = ∫ (t : ℝ) in 0..1, f t

Integrating a real function over the uniform unit interval.

@[simp]
theorem ProbabilityTheory.Copula.integral_unit_pow (n : ℕ) :
∫ (u : ↑unitInterval), ↑u ^ n = 1 / (↑n + 1)
theorem ProbabilityTheory.Copula.integral_eval {d : ℕ} (C : Copula d) (i : Fin d) (f : ↑unitInterval → ℝ) (hf : Measurable f) :
∫ (x : Fin d → ↑unitInterval), f (x i) ∂C.toMeasure = ∫ (u : ↑unitInterval), f u
@[simp]
theorem ProbabilityTheory.Copula.integral_coe_eval {d : ℕ} (C : Copula d) (i : Fin d) :
∫ (x : Fin d → ↑unitInterval), ↑(x i) ∂C.toMeasure = 1 / 2
@[simp]
theorem ProbabilityTheory.Copula.integral_sq_eval {d : ℕ} (C : Copula d) (i : Fin d) :
∫ (x : Fin d → ↑unitInterval), ↑(x i) ^ 2 ∂C.toMeasure = 1 / 3
theorem ProbabilityTheory.Copula.integral_comonotonic {d : ℕ} (f : (Fin d → ↑unitInterval) → ℝ) (hf : Measurable f) :
∫ (x : Fin d → ↑unitInterval), f x ∂(comonotonic d).toMeasure = ∫ (u : ↑unitInterval), f fun (x : Fin d) => u
theorem ProbabilityTheory.Copula.integral_independence_mul (f g : ↑unitInterval → ℝ) :
∫ (x : Fin 2 → ↑unitInterval), f (x 0) * g (x 1) ∂(independence 2).toMeasure = (∫ (u : ↑unitInterval), f u) * ∫ (v : ↑unitInterval), g v