R₅₄₉₅-E(4405 − 5495) plane likelihood for a simulated CHORIZOS run. The input U_J B_J V _J J H K_s photometry corresponds to a SED with input T_eff = 30 000 K, LC = 5, MW-metallicity, E(4405 − 5495) = 1.0, R₅₄₉₅ = 4.0 at a distance of 10 pc with uncertainties of 0.01 mag for each filter. The output has E(4405 − 5495) = 1.0003 ± 0.0067, R₅₄₉₅ = 3.999 ± 0.039, A₅₄₉₅ = 4.0002 ± 0.0151, and = 4.0313 ± 0.0151 (see Eq. (C.1)). We note how the relative uncertainties of A₅₄₉₅ and (0.38%) are smaller than either that of E(4405 − 5495) (0.67%) or R₅₄₉₅ (0.98%) due to the strong anticorrelation () between the latter two quantities.