Top: comparison of the 3D Lyα forest power spectrum, P(k). Middle: comparison of the 3D Lyα forest power spectrum ratios, P_mock(k)/P_ref(k), between the predicted and reference power spectra. Bottom: comparison of cross-correlation coefficients, C(k), between the reference Lyα forest and the predictions from the different tested models. In each panel, the investigated reference simulation summary statistics are shown as a solid red line, while the prediction by the standard FGPA is displayed as a dashed yellow line, the FGPA with velocity bias as a dotted purple line, the FGPA with velocity and threshold bias as a dash-dotted black line, the nonlocal FGPA as a dashed green line, and the nonlocal FGPA with stochasticity as a dash-dotted blue line. In the mid panel, the gray shaded areas stand for 1%,2%,5%, and 10% deviations, from darker to lighter. In the bottom panel, the gray shaded areas stand for 5% and 10% deviations, from darker to lighter.