Joint 1σ error ellipses for the parameters { α,γ,σ } of the scaling relation , obtained from the Fisher-matrix analysis of power spectra P(k), and P_L(k) defined in Sect. 2.3. Results are shown in real (shaded area) and redshift (dotted lines) space. The estimates of these spectra are obtained within the full-luminosity range and using Fourier modes in the interval 0.02 < k/(h Mpc^-1) < 0.2. The solid contours represent the results using the XLF. The right block of panels shows the results using after marginalizing over the amplitude of the power spectra. The left block shows the results using the full shape. The color of the first row is meant to highlight the results obtained with the luminosity power spectrum.