{
  "scope": "Educational nonspinning scattering-angle discrepancy calibration; not an EOB Hamiltonian or waveform calibration",
  "data": "arXiv:2507.08071v1 ancillary ScatteringAngles.dat; v2 bytes independently match",
  "partition_basis": "Metadata-only whole mass-ratio groups; chosen before examining validation/test target residuals",
  "mass_ratio_convention": "q=m1/m2>=1; map numerical near-integer q to its nearest integer within 0.001",
  "spin_tolerance": 0.000001,
  "gamma_training_domain": [1.0199, 1.16],
  "training_q": [1, 4, 7],
  "validation_q": [3, 6],
  "test_q": [2, 5, 8, 9, 10],
  "stress": "Spinning rows are unsupported; nonspinning rows outside the energy training domain are diagnostic only where the Schwarzschild scattering baseline exists. Failure of that baseline is not a binary capture criterion.",
  "target": "Mean of the two individual initial-CoM scattering angles, (theta1+theta2)/2; distinct from the EOB relative angle for unequal masses",
  "baseline": "Exact timelike Schwarzschild geodesic at effective energy gamma and orbital j=(J_ADM/M^2-chi1z*(q/(1+q))^2-chi2z/(1+q)^2)/nu, plus the finite-mass 2PM correction 3*pi*(5*gamma^2-1)*(1/Gamma-1)/(4*j^2). Restrict inputs to j>j_critical(gamma). For the fitted nominally nonspinning data the tiny residual spins are included in this angular-momentum conversion, not in the spinless scattering model.",
  "correction": "nu*(4/j)^3 times a polynomial in x=4/j, t=(gamma-1)/0.1, and nu; preserves exact Schwarzschild test-mass scattering and the known full 1PM/2PM angles at fixed gamma",
  "candidate_features": {
    "constant": ["1"],
    "linear": ["1", "x", "t", "nu"],
    "quadratic": ["1", "x", "t", "nu", "x*x", "x*t", "t*t"]
  },
  "selection": "Smallest weighted validation RMS; if relative difference is below 0.01, prefer fewer coefficients",
  "weighting": "Angles converted from degrees to radians once. Positive scale=max((lower1+lower2)/2,(upper1+upper2)/2); weighted RMS=sqrt(mean((residual/scale)^2)). Bounds are propagated without assuming independent Gaussian errors.",
  "acceptance": "An illustrative one-percent accuracy target: every training, validation and blind-test angle must have absolute fractional residual <=0.01. Failing any partition rejects the candidate; this target is not a claim about a production model or a statistical confidence level.",
  "test_rule": "Evaluate blind test only once after candidate and all refinement decisions are locked; report failure rather than tune on test",
  "covariance": "Report least-squares curvature and parameter sensitivity; authors' asymmetric error estimates are not asserted to be Gaussian standard deviations"
}