Probability density function of X_off, P (Eq. (B.2)). Each panel shows the distribution at a specific redshift. Each set is divided in mass slices, identified by color. Scatter points indicate the data, while straight lines represent the modified Schechter model (14). For clarity, each line and its fit are shifted by 0.2 dex along both axes. This means that the coefficient C₀ assumes values ( + 0.6, +0.4, +0.2, 0.0, −0.2, −0.4), while C₁ is ( − 0.6, −0.4, −0.2, 0.0, +0.2, +0.4). The red line is not shifted, and thus is the one with the correct normalization.