Comparison of separation ratios r₀₂ of Model A1 and B1. Top panel: comparison at the same n where the fit is good with a χ² = 0.43; bottom panel: fit at the same frequencies which is equivalent to comparing inner phase shift differences which would agree were the two models to have the same interior structure. The continuous curves are the inner phase shift differences δ₂(ν) − δ₀(ν) for the 2 models.