def fisherInfo1 (J : ℕ) (m : EquicorrModel) : ℝ := ↑J / (m.τ ^ 2 * (1 + m.r * (↑J - 1)))
thesis/CESProofs/CurvatureRoles/CorrelationRobust.lean:85
Correlation robustness of CES (Paper 1, Section 7):