Galaxy clustering ratio on a scale of R = 5   h^-1 Mpc and a correlation length n = 3, as estimated from real VIPERS data (squares) in two distinct redshift bins. Measurements for the individual VIPERS fields W1 (diamonds) and W4 (triangle) are also shown. The best fit theoretical model (cf. Eq. (8)) accounting for all non-linear and observational effects is given by the solid line. For comparison, we also display the corresponding linear theory prediction (dotted line) for the best fit cosmological parameters and the non-linear prediction when the corrections for peculiar motions and redshift errors are not included (short-dashed line). Error bars have been estimated from the standard deviation among the 31(/ 26)L_gV mock VIPERS surveys of the W1/W4 fields, which include the contribution from cosmic variance. We also plot the observed and predicted values of when a “wrong” cosmology with slightly higher matter density Ω_m0 = 0.4 is assumed (open squares and long-dashed curve, respectively). The divergence of observations and theory shows that this is not the best-fitting model, resulting in a low likelihood. For clarity, all data points have been slightly shifted along the abscissa.