Top: Comparison between the fraction of cases that a measurement is in agreement with the intrinsic true value, f_comp, as a function of the confidence level. Bottom: Applied correction factor to uncertainty. The uncorrected f_comp is shown in colored solid lines, which IGM+z in green, IGM-z in blue and NoIGM in yellow. f_comp after the correction is shown in colored dots. In each panel a different output property is shown. In the first row z_max, V_exp and N_H from left to right. In the second row τ_a, EW_in, W_in, from left to right. In the third row $f_{\text{esc}}^{1\stackrel{\circ }{\mathrm{A}}},f_{\text{esc}}^{2\stackrel{\circ }{\mathrm{A}}}$, and $f_{\text{esc}}^{4\stackrel{\circ }{\mathrm{A}}}$ from left to right. The diagonal black dashed lines show the 1:1±10% relation. Computed using 10⁴ line profiles with quality W_g = 0.5 Å, Δλ_Pix = 0.1 Å and S/N_p = 10.