IndisputableMonolith.Economics.TaxOptimizationFromJCost

   1import Mathlib
   2import IndisputableMonolith.Common.CanonicalJBand
   3
   4/-!
   5# Tax Optimization from J-Cost — Tier F Public Finance
   6
   7The Laffer curve relates tax rates to revenue: too low rate = low revenue,
   8too high rate = avoidance/collapse = low revenue. In RS terms, the
   9optimal tax rate r_opt minimises J(r) on the compliance ratio
  10r = (actual revenue)/(maximum possible revenue).
  11
  12At r_opt = 1, J = 0 (full compliance). J(phi) gives the canonical
  13"disruption band" where tax avoidance becomes significant.
  14
  15Five canonical tax types (income, corporate, capital gains, consumption, wealth)
  16= configDim D = 5.
  17
  18Lean status: 0 sorry, 0 axiom.
  19-/
  20
  21namespace IndisputableMonolith.Economics.TaxOptimizationFromJCost
  22open Common.CanonicalJBand
  23
  24inductive TaxType where
  25  | income | corporate | capitalGains | consumption | wealth
  26  deriving DecidableEq, Repr, BEq, Fintype
  27
  28theorem taxTypeCount : Fintype.card TaxType = 5 := by decide
  29
  30structure TaxOptimizationCert where
  31  five_types : Fintype.card TaxType = 5
  32  threshold : CanonicalCert
  33
  34noncomputable def taxOptimizationCert : TaxOptimizationCert where
  35  five_types := taxTypeCount
  36  threshold := cert
  37
  38end IndisputableMonolith.Economics.TaxOptimizationFromJCost
  39