Left: radial number density of galaxies in the simulated W4 field before (diamonds) and after (triangles) implementing the radial selection function of VIPERS PDR-1. Right: estimations of the variance σ_g,R (upper), correlation function ξ_g,R(3R) (centre), and clustering ratio η_g,R(3R) (lower) from the true population of galaxies in the W4 field (diamonds) and from the sub-sample with the same VIPERS radial density profile (triangles) are shown as a function of the filtering scale R. Squares show estimates obtained after correcting the relevant statistical quantities for shot noise, using the local Poisson model (Layser 1956).