def cesGamePayoff (ρ : ℝ) (x₁ x₂ : ℝ) (e : ℝ) (i : Fin 2) : ℝ := ((1 / 2 : ℝ) * (x₁ ^ ρ + x₂ ^ ρ)) ^ (1 / ρ) - e * if i = 0 then x₁ else x₂
thesis/CESProofs/CurvatureRoles/Strategic.lean:94
Strategic independence of CES (Paper 1, Sections 7-8):