Scale dependence of the matter correlation functions for a realistic cosmological model (cosmological parameters derived from Plank, Planck Collaboration VI 2020) for the 3D density and the projected density (for a uniformly sampled survey with a depth of about 800 h⁻¹Mpc between z = 0.75 and z = 1.25). The top panel shows (solid blue line) and (dashed red line) for the 3D density field, and the bottom panel shows and for the projected density. In both cases, the average value of the first moment of the two-point correlation function is dominated by large-distance contributions, whereas short-distance contributions dominate the second moment, assuming survey sizes of about 100 h⁻¹ Mpc or above.