Cross-covariance between number counts and clustering. For better visualisation, we used redshift bins of width Δz = 0.2 for counts and Δz = 0.5 and a single richness bin for the 2PCF. Left: Auto- and cross-correlation matrix of number counts and clustering, computed from 1000 mocks. Right: Log-likelihood residuals for number counts and clustering for each one of the 1000 light cones, with respect to the mean value assuming the fiducial model parameters.