Difference of mass-loading factors Δη and metal-loading factors ζ_w inferred from the Bayesian analysis, and observed Z_g in the bottom panel, as a function of M_star on the left, and as a function of μ_g on the right. In the two upper panels, the best-fit Bayesian values are shown as filled symbols (circles or squares according to the Δη prior), with error bars corresponding to the ±1σ excursion, which is also illustrated by light-gray shaded regions. The rightmost point (magenta circle) in the top and middle right panels corresponds to the “extra” high-μ_g bin shown in Fig. 6. In the top panels, a horizontal dashed line illustrates the “equilibrium solution” with Δη = α. In the top left panel, the (purple) dashed curve is a linear power-law fit of Δη to log(M_star), while the dashed curve in the top right panel shows Eq. (27), with d log M_g/d log M_star = 0.72, as found in Paper II. The fits to the curves for ζ_w in the middle panels are cubic: log(ζ_w) as a function of log(M_star) in the left panel, and ζ_w as a function of F_g in the right. In the lower panels, observed MAGMA Z_g are shown as small filled circles, color coded by gas fraction, while the Z_g medians and 1σ deviations are shown by large (black) filled circles and error bars. The dashed curves in the lower panels correspond to the calculation of Z_g based on the fits in the upper panels (as a function of μ_g on the left, and log(M_star) on the right): the long-dashed curves (dark orange) correspond to the Δη ≥ 0 priors, while the short-dashed ones (purple) to the “symmetric” priors. The green curves in the left panels are described in the text, obtained by fitting individual galaxy Δη and ζ_w calculated using Eqs. (27) and (28).