OAI/Combinatorics/DiscreteConvexity/CoveringSampledFamilies.lean

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9 declarations, 0 contain sorry, 0 declared as axioms

Deterministic covers from a pair-sampling outcome

Every sampling outcome gives a cover. The cost bounds count generators with multiplicity, indexed by ordered pairs or injective ordered tuples. No independence or probability estimate is needed for these pointwise statements.

  1. def OAI.TalagrandDiscreteConvexity.Covering.pairUnion line 23

    Source documentation

    The generator produced by a sampled ordered pair.

    def pairUnion {H : Family V} (p : PairIndex H) : Finset V := p.1.val ∪ p.2.val

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.PairIndex

  2. def OAI.TalagrandDiscreteConvexity.Covering.sampledFamily line 26

    Source documentation

    Duplicate unions are identified in the family of sampled generators.

    noncomputable def sampledFamily (H : Family V) (sample : Sample H) : Family V :=
    …

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.Sample

  3. def OAI.TalagrandDiscreteConvexity.Covering.residualFamily line 31

    Source documentation

    An injective tuple contributes a residual generator exactly when all of its ordered pair indices were avoided.

    noncomputable def residualFamily (H : Family V) (m : ℕ) (sample : Sample H) :
        Family V := by
    …

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.Sample

  4. theorem OAI.TalagrandDiscreteConvexity.Covering.mem_sampledFamily line 37
  5. theorem OAI.TalagrandDiscreteConvexity.Covering.mem_residualFamily line 42
  6. theorem OAI.TalagrandDiscreteConvexity.Covering.cost_sampledFamily_le line 50

    Source documentation

    Counting each sampled ordered pair separately bounds the family cost.

    theorem cost_sampledFamily_le (H : Family V) (sample : Sample H)
        {rho : ℝ} (hrho : 0 ≤ rho) :
        cost rho (sampledFamily H sample) ≤
          ∑ p ∈ sample, rho ^ (pairUnion p).card := by
    …

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.Sample, OAI.TalagrandDiscreteConvexity.cost, OAI.TalagrandDiscreteConvexity.Covering.sampledFamily, OAI.TalagrandDiscreteConvexity.Covering.pairUnion

  7. theorem OAI.TalagrandDiscreteConvexity.Covering.cost_residualFamily_le line 61

    Source documentation

    Counting each avoiding tuple separately bounds the residual cost. The indicator has the same argument order as the sampling law.

    theorem cost_residualFamily_le (H : Family V) (m : ℕ) (sample : Sample H)
        {rho : ℝ} (hrho : 0 ≤ rho) :
        cost rho (residualFamily H m sample) ≤
          ∑ f : EdgeTuple H m,
            if Disjoint sample (tuplePairs f) then rho ^ (tupleUnion f).card else 0 := by
    …

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.Sample, OAI.TalagrandDiscreteConvexity.cost, OAI.TalagrandDiscreteConvexity.Covering.residualFamily, OAI.TalagrandDiscreteConvexity.Covering.EdgeTuple, OAI.TalagrandDiscreteConvexity.Covering.tuplePairs, OAI.TalagrandDiscreteConvexity.Covering.tupleUnion

  8. theorem OAI.TalagrandDiscreteConvexity.Covering.exists_regular_tuple line 79

    Source documentation

    A large contained-edge family can be enumerated injectively inside the regular edges, provided the set avoids the initial generators.

    theorem exists_regular_tuple {H C0 : Family V} {m : ℕ} {S : Finset V}
        (hm : m ≤ (H.filter (fun e => e ⊆ S)).card)
        (h0 : ¬∃ I ∈ C0, I ⊆ S) :
        ∃ f : EdgeTuple (regularFamily H C0) m, ∀ i, (f.val i).val ⊆ S := by
    …

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.EdgeTuple, OAI.TalagrandDiscreteConvexity.Covering.regularFamily

  9. theorem OAI.TalagrandDiscreteConvexity.Covering.covers_sampled_residual line 106

    Source documentation

    Every pair-sampling outcome covers each set containing sufficiently many original edges. This includes m = 0 and empty edge families.

    theorem covers_sampled_residual [Fintype V] (H C0 : Family V) (m : ℕ)
        (sample : Sample (regularFamily H C0)) :
        Covers (C0 ∪ sampledFamily (regularFamily H C0) sample ∪
          residualFamily (regularFamily H C0) m sample) (denseFamily H m) := by
    …

    Mentions: OAI.TalagrandDiscreteConvexity.Family, OAI.TalagrandDiscreteConvexity.Covering.Sample, OAI.TalagrandDiscreteConvexity.Covering.regularFamily, OAI.TalagrandDiscreteConvexity.Covers, OAI.TalagrandDiscreteConvexity.Covering.sampledFamily, OAI.TalagrandDiscreteConvexity.Covering.residualFamily, OAI.TalagrandDiscreteConvexity.Covering.denseFamily