mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f : ℕ → Ω → E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
hf : StronglyAdapted ℱ f
hf_int : ∀ (n : ℕ), Integrable (f n) μ
inst✝ : SigmaFiniteFiltration μ ℱ
i✝ j : ℕ
hij : i✝ ≤ j
i : ℕ
x✝ : i ∈ Finset.range j
⊢ Integrable (f (i + 1) - f i - μ[f (i + 1) - f i | ↑ℱ i]) μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Predictable

Goal state before:
pp: case neg
Ω : Type u_1
m✝ : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m✝
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
this : MeasurableSpace (ℕ × Ω) := ⋯
X : ℕ → ℕ × Ω → E := ⋯
Y : ℕ → ℕ × Ω → E := ⋯
m : ℕ
s : E
n : ℕ
hmk : m < n + 1
⊢ MeasurableSet (Function.curry (X m) 0 ⁻¹' {s})

Tactic:
let : MeasurableSpace Ω := 𝓕 0

Goal state after:
case neg
Ω : Type u_1
m✝ : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m✝
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
this✝ : MeasurableSpace (ℕ × Ω) := 𝓕.predictable
X : ℕ → ℕ × Ω → E :=
  fun m x ↦
    match x.1 with
    | 0 => (h₀.approx m) x.2
    | n.succ => (⋯.approx m) x.2
Y : ℕ → ℕ × Ω → E := fun m x ↦ if x.1 ≤ m then X m x else X m (0, x.2)
m : ℕ
s : E
n : ℕ
hmk : m < n + 1
this : MeasurableSpace Ω := ↑𝓕 0
⊢ MeasurableSet (Function.curry (X m) 0 ⁻¹' {s})
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁴ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f g : ι → Ω → E
ℱ : Filtration ι m0
inst✝¹ : CompleteSpace E
inst✝ : LE E
hf : Supermartingale f ℱ μ
hg : StronglyAdapted ℱ g
h_eq : ∀ (t : ι), f t =ᵐ[μ] g t
⊢ Supermartingale g ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
f g : ι → Ω → E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : Preorder E
inst✝ : AddLeftMono E
hf : Supermartingale f ℱ μ
hg : Supermartingale g ℱ μ
⊢ Supermartingale (f + g) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Predictable

Goal state before:
pp: Ω : Type u_1
m✝ : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m✝
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
this : MeasurableSpace (ℕ × Ω) := 𝓕.predictable
X : ℕ → ℕ × Ω → E :=
  fun m x ↦
    match x.1 with
    | 0 => (h₀.approx m) x.2
    | n.succ => (⋯.approx m) x.2
Y : ℕ → ℕ × Ω → E := fun m x ↦ if x.1 ≤ m then X m x else X m (0, x.2)
m : ℕ
⊢ (↑(Finset.range (m + 1))).Finite

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
f : ι → Ω → E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : Preorder E
inst✝ : AddLeftMono E
hf : Supermartingale f ℱ μ
⊢ Submartingale (-f) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁴ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f g : ι → Ω → E
ℱ : Filtration ι m0
inst✝¹ : CompleteSpace E
inst✝ : LE E
hf : Submartingale f ℱ μ
hg : StronglyAdapted ℱ g
h_eq : ∀ (t : ι), f t =ᵐ[μ] g t
⊢ Submartingale g ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f : ℕ → Ω → E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
hf : StronglyAdapted ℱ f
hf_int : ∀ (n : ℕ), Integrable (f n) μ
inst✝ : SigmaFiniteFiltration μ ℱ
i j : ℕ
hij : i ≤ j
k : ℕ
x✝ : k ∈ Finset.range j
⊢ Integrable (f (k + 1) - f k) μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
f g : ι → Ω → E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : Preorder E
inst✝ : AddLeftMono E
hf : Submartingale f ℱ μ
hg : Submartingale g ℱ μ
⊢ Submartingale (f + g) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f : ℕ → Ω → E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
hf : StronglyAdapted ℱ f
hf_int : ∀ (n : ℕ), Integrable (f n) μ
inst✝ : SigmaFiniteFiltration μ ℱ
i j : ℕ
hij : i ≤ j
⊢ μ[martingalePart f ℱ μ j | ↑ℱ i] =ᵐ[μ]
    f 0 + ∑ k ∈ Finset.range j, (μ[f (k + 1) - f k | ↑ℱ i] - μ[μ[f (k + 1) - f k | ↑ℱ k] | ↑ℱ i])

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
f : ι → Ω → E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : Preorder E
inst✝ : AddLeftMono E
hf : Submartingale f ℱ μ
⊢ Supermartingale (-f) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁸ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
ℱ : Filtration ι m0
inst✝⁵ : CompleteSpace E
inst✝⁴ : PartialOrder E
inst✝³ : IsOrderedAddMonoid E
inst✝² : IsOrderedModule ℝ E
inst✝¹ : ClosedIciTopology E
inst✝ : SigmaFiniteFiltration μ ℱ
f : ι → Ω → E
hf : Submartingale f ℱ μ
i j : ι
hij : i ≤ j
s : Set Ω
hs : MeasurableSet s
⊢ ∫ (ω : Ω) in s, f i ω ∂μ ≤ ∫ (ω : Ω) in s, f j ω ∂μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
f g : ι → Ω → E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : Preorder E
inst✝ : AddLeftMono E
hf : Submartingale f ℱ μ
hg : Supermartingale g ℱ μ
⊢ Submartingale (f - g) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁸ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
ℱ : Filtration ι m0
inst✝⁵ : CompleteSpace E
inst✝⁴ : Lattice E
inst✝³ : ContinuousSup E
inst✝² : HasSolidNorm E
inst✝¹ : IsOrderedAddMonoid E
inst✝ : IsOrderedModule ℝ E
f g : ι → Ω → E
hf : Submartingale f ℱ μ
hg : Submartingale g ℱ μ
⊢ Submartingale (f ⊔ g) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Predictable

Goal state before:
pp: Ω : Type u_1
m✝ : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m✝
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
this : MeasurableSpace (ℕ × Ω) := 𝓕.predictable
X : ℕ → ℕ × Ω → E :=
  fun m x ↦
    match x.1 with
    | 0 => (h₀.approx m) x.2
    | n.succ => (⋯.approx m) x.2
Y : ℕ → ℕ × Ω → E := fun m x ↦ if x.1 ≤ m then X m x else X m (0, x.2)
m : ℕ
e : E
he : e ∈ Set.range (Y m)
n : ℕ
ω : Ω
hnω : Y m (n, ω) = e
⊢ (if n ≤ m then n else 0) ∈ Finset.range (m + 1)

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝¹ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
inst✝ : SigmaFiniteFiltration μ ℱ
f : ι → Ω → ℝ
hadp : StronglyAdapted ℱ f
hint : ∀ (i : ι), Integrable (f i) μ
hf : ∀ (i j : ι), i ≤ j → ∀ (s : Set Ω), MeasurableSet s → ∫ (ω : Ω) in s, f i ω ∂μ ≤ ∫ (ω : Ω) in s, f j ω ∂μ
i j : ι
hij : i ≤ j
this : f i ≤ᵐ[μ.trim ⋯] μ[f j | ↑ℱ i]
⊢ f i ≤ᵐ[μ] μ[f j | ↑ℱ i]

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Predictable

Goal state before:
pp: Ω : Type u_1
m✝ : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m✝
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
this : MeasurableSpace (ℕ × Ω) := 𝓕.predictable
X : ℕ → ℕ × Ω → E :=
  fun m x ↦
    match x.1 with
    | 0 => (h₀.approx m) x.2
    | n.succ => (⋯.approx m) x.2
Y : ℕ → ℕ × Ω → E := fun m x ↦ if x.1 ≤ m then X m x else X m (0, x.2)
m : ℕ
e : E
he : e ∈ Set.range (Y m)
n : ℕ
ω : Ω
hnω : Y m (n, ω) = e
⊢ Function.curry (X m) (if n ≤ m then n else 0) ω = e

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f : ℕ → Ω → E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
hf : StronglyAdapted ℱ f
hf_int : ∀ (n : ℕ), Integrable (f n) μ
inst✝ : SigmaFiniteFiltration μ ℱ
i j : ℕ
hij : i ≤ j
h_eq_sum :
  μ[martingalePart f ℱ μ j | ↑ℱ i] =ᵐ[μ]
    f 0 + ∑ k ∈ Finset.range j, (μ[f (k + 1) - f k | ↑ℱ i] - μ[μ[f (k + 1) - f k | ↑ℱ k] | ↑ℱ i])
⊢ ∀ (k : ℕ), i ≤ k → μ[f (k + 1) - f k | ↑ℱ i] - μ[μ[f (k + 1) - f k | ↑ℱ k] | ↑ℱ i] =ᵐ[μ] 0

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝¹ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
inst✝ : SigmaFiniteFiltration μ ℱ
f : ι → Ω → ℝ
hadp : StronglyAdapted ℱ f
hint : ∀ (i : ι), Integrable (f i) μ
hf : ∀ (i j : ι), i ≤ j → ∀ (s : Set Ω), MeasurableSet s → ∫ (ω : Ω) in s, f i ω ∂μ ≤ ∫ (ω : Ω) in s, f j ω ∂μ
i j : ι
hij : i ≤ j
this : 0 ≤ᵐ[μ.trim ⋯] μ[f j | ↑ℱ i] - f i
⊢ f i ≤ᵐ[μ.trim ⋯] μ[f j | ↑ℱ i]

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝¹ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
inst✝ : SigmaFiniteFiltration μ ℱ
f : ι → Ω → ℝ
hadp : StronglyAdapted ℱ f
hint : ∀ (i : ι), Integrable (f i) μ
hf : ∀ (i j : ι), i ≤ j → ∀ (s : Set Ω), MeasurableSet s → ∫ (ω : Ω) in s, f i ω ∂μ ≤ ∫ (ω : Ω) in s, f j ω ∂μ
⊢ Submartingale f ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁶ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
ℱ : Filtration ι m0
inst✝³ : CompleteSpace E
inst✝² : PartialOrder E
inst✝¹ : IsOrderedAddMonoid E
inst✝ : SigmaFiniteFiltration μ ℱ
f : ι → Ω → E
hadp : StronglyAdapted ℱ f
hint : ∀ (i : ι), Integrable (f i) μ
hf : ∀ (i j : ι), i ≤ j → 0 ≤ᵐ[μ] μ[f j - f i | ↑ℱ i]
⊢ Submartingale f ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : PartialOrder E
inst✝ : IsOrderedAddMonoid E
f : ι → Ω → E
hf : Submartingale f ℱ μ
i j : ι
hij : i ≤ j
⊢ 0 ≤ᵐ[μ] μ[f j - f i | ↑ℱ i]

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f : ℕ → Ω → E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
hf : StronglyAdapted ℱ f
hf_int : ∀ (n : ℕ), Integrable (f n) μ
inst✝ : SigmaFiniteFiltration μ ℱ
i j : ℕ
hij : i ≤ j
h_eq_sum :
  μ[martingalePart f ℱ μ j | ↑ℱ i] =ᵐ[μ]
    f 0 + ∑ k ∈ Finset.range j, (μ[f (k + 1) - f k | ↑ℱ i] - μ[μ[f (k + 1) - f k | ↑ℱ k] | ↑ℱ i])
h_ge : ∀ (k : ℕ), i ≤ k → μ[f (k + 1) - f k | ↑ℱ i] - μ[μ[f (k + 1) - f k | ↑ℱ k] | ↑ℱ i] =ᵐ[μ] 0
⊢ ∀ k < i,
    μ[f (k + 1) - f k | ↑ℱ i] - μ[μ[f (k + 1) - f k | ↑ℱ k] | ↑ℱ i] =ᵐ[μ] f (k + 1) - f k - μ[f (k + 1) - f k | ↑ℱ k]

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
E : Type u_2
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
f g : ι → Ω → E
ℱ : Filtration ι m0
inst✝² : CompleteSpace E
inst✝¹ : Preorder E
inst✝ : AddLeftMono E
hf : Supermartingale f ℱ μ
hg : Submartingale g ℱ μ
⊢ Supermartingale (f - g) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
F : Type u_4
inst✝⁴ : NormedAddCommGroup F
inst✝³ : PartialOrder F
inst✝² : NormedSpace ℝ F
inst✝¹ : CompleteSpace F
inst✝ : IsOrderedModule ℝ F
f : ι → Ω → F
c : ℝ
hc : 0 ≤ c
hf : Supermartingale f ℱ μ
i j : ι
hij : i ≤ j
ω : Ω
hω : μ[c • f j | ↑ℱ i] ω = (c • μ[f j | ↑ℱ i]) ω
⊢ μ[f j | ↑ℱ i] ω ≤ f i ω → μ[(c • f) j | ↑ℱ i] ω ≤ (c • f) i ω

Tactic:
hle

Goal state after:
Ω : Type u_1
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
F : Type u_4
inst✝⁴ : NormedAddCommGroup F
inst✝³ : PartialOrder F
inst✝² : NormedSpace ℝ F
inst✝¹ : CompleteSpace F
inst✝ : IsOrderedModule ℝ F
f : ι → Ω → F
c : ℝ
hc : 0 ≤ c
hf : Supermartingale f ℱ μ
i j : ι
hij : i ≤ j
ω : Ω
hω : μ[c • f j | ↑ℱ i] ω = (c • μ[f j | ↑ℱ i]) ω
hle : μ[f j | ↑ℱ i] ω ≤ f i ω
⊢ μ[(c • f) j | ↑ℱ i] ω ≤ (c • f) i ω
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝⁵ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
F : Type u_4
inst✝⁴ : NormedAddCommGroup F
inst✝³ : PartialOrder F
inst✝² : NormedSpace ℝ F
inst✝¹ : CompleteSpace F
inst✝ : IsOrderedModule ℝ F
f : ι → Ω → F
c : ℝ
hc : 0 ≤ c
hf : Supermartingale f ℱ μ
⊢ Supermartingale (c • f) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝ : Preorder ι
f : Filtration ι m
i j : ι
⊢ MeasurableSet {ω | (fun x ↦ ↑i) ω ≤ ↑j}

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝⁶ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
F : Type u_4
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : PartialOrder F
inst✝³ : NormedSpace ℝ F
inst✝² : CompleteSpace F
inst✝¹ : IsOrderedModule ℝ F
inst✝ : IsOrderedAddMonoid F
f : ι → Ω → F
c : ℝ
hc : c ≤ 0
hf : Supermartingale f ℱ μ
⊢ Submartingale (c • f) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Predictable

Goal state before:
pp: Ω : Type u_1
m✝ : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m✝
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
this : MeasurableSpace (ℕ × Ω) := 𝓕.predictable
X : ℕ → ℕ × Ω → E :=
  fun m x ↦
    match x.1 with
    | 0 => (h₀.approx m) x.2
    | n.succ => (⋯.approx m) x.2
Y : ℕ → ℕ × Ω → E := fun m x ↦ if x.1 ≤ m then X m x else X m (0, x.2)
n : ℕ
ω : Ω
m : ℕ
hm : n ≤ m
⊢ { toFun := Y m, measurableSet_fiber' := ⋯, finite_range' := ⋯ } (n, ω) = X m (n, ω)

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝¹ : Preorder ι
f : Filtration ι m
τ : Ω → WithTop ι
inst✝ : PredOrder ι
hτ : IsStoppingTime f τ
i : ι
hi_min : IsMin i
this : {ω | τ ω < ↑i} = ∅
⊢ MeasurableSet {ω | τ ω < ↑i}

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝⁶ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
F : Type u_4
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : PartialOrder F
inst✝³ : IsOrderedAddMonoid F
inst✝² : NormedSpace ℝ F
inst✝¹ : CompleteSpace F
inst✝ : IsOrderedModule ℝ F
f : ι → Ω → F
c : ℝ
hc : 0 ≤ c
hf : Submartingale f ℱ μ
⊢ Submartingale (c • f) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
inst✝⁶ : Preorder ι
m0 : MeasurableSpace Ω
μ : Measure Ω
ℱ : Filtration ι m0
F : Type u_4
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : PartialOrder F
inst✝³ : IsOrderedAddMonoid F
inst✝² : NormedSpace ℝ F
inst✝¹ : CompleteSpace F
inst✝ : IsOrderedModule ℝ F
f : ι → Ω → F
c : ℝ
hc : c ≤ 0
hf : Submartingale f ℱ μ
⊢ Supermartingale (c • f) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝¹ : Preorder ι
f : Filtration ι m
τ : Ω → WithTop ι
inst✝ : PredOrder ι
hτ : IsStoppingTime f τ
i : ι
hi_min : ¬IsMin i
⊢ {ω | τ ω < ↑i} = τ ⁻¹' Set.Iic ↑(Order.pred i)

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Predictable

Goal state before:
pp: Ω : Type u_1
m : MeasurableSpace Ω
E : Type u_3
inst✝ : TopologicalSpace E
𝓕 : Filtration ℕ m
u : ℕ → Ω → E
h₀ : StronglyMeasurable (u 0)
h : ∀ (n : ℕ), StronglyMeasurable (u (n + 1))
⊢ IsStronglyPredictable 𝓕 u

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
f : ℕ → Ω → E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
hf : StronglyAdapted ℱ f
hf_int : ∀ (n : ℕ), Integrable (f n) μ
inst✝ : SigmaFiniteFiltration μ ℱ
⊢ Martingale (martingalePart f ℱ μ) ℱ μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝¹ : Preorder ι
f : Filtration ι m
τ : Ω → WithTop ι
inst✝ : PredOrder ι
hτ : IsStoppingTime f τ
i : ι
⊢ MeasurableSet {ω | τ ω < ↑i}

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
m0 : MeasurableSpace Ω
μ : Measure Ω
𝒢 : Filtration ℕ m0
inst✝ : IsFiniteMeasure μ
f : ℕ → Ω → ℝ
hadp : StronglyAdapted 𝒢 f
hint : ∀ (i : ℕ), Integrable (f i) μ
hf : ∀ (i : ℕ) (s : Set Ω), MeasurableSet s → ∫ (ω : Ω) in s, f i ω ∂μ ≤ ∫ (ω : Ω) in s, f (i + 1) ω ∂μ
⊢ Submartingale f 𝒢 μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝¹ : Preorder ι
inst✝ : InfSet ι
u : ι → Ω → β
n m : ι
⊢ hittingBtwn u ∅ n m = fun x ↦ m

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝¹ : Preorder ι
inst✝ : InfSet ι
u : ι → Ω → β
n : ι
⊢ hittingAfter u ∅ n = fun x ↦ ⊤

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_4
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
n m : ι
⊢ hittingBtwn u Set.univ n m = fun x ↦ min n m

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Basic

Goal state before:
pp: Ω : Type u_1
m0 : MeasurableSpace Ω
μ : Measure Ω
𝒢 : Filtration ℕ m0
inst✝ : IsFiniteMeasure μ
f : ℕ → Ω → ℝ
hadp : StronglyAdapted 𝒢 f
hint : ∀ (i : ℕ), Integrable (f i) μ
hf : ∀ (i : ℕ) (s : Set Ω), MeasurableSet s → ∫ (ω : Ω) in s, f (i + 1) ω ∂μ ≤ ∫ (ω : Ω) in s, f i ω ∂μ
⊢ Supermartingale f 𝒢 μ

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
inst✝ : SigmaFiniteFiltration μ ℱ
f g : ℕ → Ω → E
hf : Martingale f ℱ μ
hg : StronglyAdapted ℱ fun n ↦ g (n + 1)
hg0 : g 0 = 0
hgint : ∀ (n : ℕ), Integrable (g n) μ
n : ℕ
h : ℕ → Ω → E := f - martingalePart (f + g) ℱ μ
hhdef : h = f - martingalePart (f + g) ℱ μ
⊢ h = predictablePart (f + g) ℱ μ - g

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_4
inst✝ : ConditionallyCompleteLattice ι
u : ι → Ω → β
n : ι
⊢ hittingAfter u Set.univ n = fun x ↦ ↑n

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n : ι
ω : Ω
m : ι
h : m < n
⊢ hittingBtwn u s n m ω = m

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
inst✝ : SigmaFiniteFiltration μ ℱ
f g : ℕ → Ω → E
hf : Martingale f ℱ μ
hg : StronglyAdapted ℱ fun n ↦ g (n + 1)
hg0 : g 0 = 0
hgint : ∀ (n : ℕ), Integrable (g n) μ
n : ℕ
h : ℕ → Ω → E := f - martingalePart (f + g) ℱ μ
hhdef : h = f - martingalePart (f + g) ℱ μ
hh : h = predictablePart (f + g) ℱ μ - g
⊢ StronglyAdapted ℱ fun n ↦ h (n + 1)

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝ : PartialOrder ι
τ : Ω → WithTop ι
f : Filtration ι m
hτ : IsStoppingTime f τ
h_countable : (Set.range τ).Countable
i : ι
⊢ {ω | τ ω = ↑i} = {ω | τ ω ≤ ↑i} \ ⋃ j ∈ Set.range τ, ⋃ (_ : j < ↑i), {ω | τ ω ≤ j}

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n m : ι
ω : Ω
⊢ hittingBtwn u s n m ω ≤ m

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n : ι
ω : Ω
m k : ι
hk₁ : k < hittingBtwn u s n m ω
hk₂ : n ≤ k
⊢ u k ω ∉ s

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n : ι
ω : Ω
k : ι
hk₁ : ↑k < hittingAfter u s n ω
hk₂ : n ≤ k
⊢ u k ω ∉ s

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n : ι
ω : Ω
m : ι
⊢ hittingBtwn u s n m ω = m ↔ (∃ j ∈ Set.Icc n m, u j ω ∈ s) → sInf (Set.Icc n m ∩ {i | u i ω ∈ s}) = m

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.HittingTime

Goal state before:
pp: Ω : Type u_1
β : Type u_2
ι : Type u_3
inst✝ : ConditionallyCompleteLinearOrder ι
u : ι → Ω → β
s : Set β
n : ι
ω : Ω
⊢ hittingAfter u s n ω = ⊤ ↔ ∀ (j : ι), n ≤ j → u j ω ∉ s

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝ : PartialOrder ι
τ : Ω → WithTop ι
f : Filtration ι m
hτ : IsStoppingTime f τ
h_countable : (Set.range τ).Countable
i : ι
⊢ MeasurableSet {ω | τ ω = ↑i}

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Martingale.Centering

Goal state before:
pp: Ω : Type u_1
E : Type u_2
m0 : MeasurableSpace Ω
μ : Measure Ω
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
ℱ : Filtration ℕ m0
inst✝¹ : CompleteSpace E
inst✝ : SigmaFiniteFiltration μ ℱ
f g : ℕ → Ω → E
hf : Martingale f ℱ μ
hg : StronglyAdapted ℱ fun n ↦ g (n + 1)
hg0 : g 0 = 0
hgint : ∀ (n : ℕ), Integrable (g n) μ
n : ℕ
⊢ martingalePart (f + g) ℱ μ n =ᵐ[μ] f n

Tactic:
by

Goal state after:
Module: Mathlib.Probability.Process.Stopping

Goal state before:
pp: Ω : Type u_1
ι : Type u_3
m : MeasurableSpace Ω
inst✝ : PartialOrder ι
τ : Ω → WithTop ι
f : Filtration ι m
hτ : IsStoppingTime f τ
h_countable : (Set.range τ).Countable
i : ι
⊢ {ω | τ ω < ↑i} = {ω | τ ω ≤ ↑i} \ {ω | τ ω = ↑i}

Tactic:
by

Goal state after: