Left panel: Marginalised 2D and 1D posterior distributions at z = 0.9 from the joint 2PCF and 3PCF analysis of the cosmological parameters h, ω_cdm, and A_s and the linear bias parameter b₁ for various 3PCF scale cuts ($r_{\min }^{3\mathrm{PCF}}$) and the η_min parameter defined in Eq. (40), fixing $r_{\min }^{2\mathrm{PCF}}=25h^{-1}\mathrm{Mpc}$. Grey contours correspond to the 2PCF-only analysis assuming a Gaussian prior on b₁ given by the 10% uncertainties around the best-fit value obtained from the joint analysis. Each panel shows the results for a different snapshot. Vertical and horizontal lines denote the fiducial values of the cosmological parameters. Right panel: Marginalised 1D and 2D posterior distributions of the same subset of model parameters for the combined analysis of 2PCF and 3PCF at z = 0.9 fixing $r_{\min }^{2\mathrm{PCF}}=25h^{-1}\mathrm{Mpc}$. The reference case of the maximal model with $r_{\min }^{3\mathrm{PCF}}=30h^{-1}\mathrm{Mpc}$ and η_min = 3 is compared to the results obtained adopting the bias relations of Eq. (16), in red, and its combination with Eq. (17), in brown.