Effect of varying the correlation in the two luminosity values’ scatter on the output stack luminosity. Top: Violin plots showing the stack luminosity for each ρ value for both the default choice of the Lyα luminosity function z ∼ 3 and the bright AGN-like version. Bottom: Output luminosity values normalised to the value at ρ = 0 to show relative changes between values of ρ. Violins are offset slightly in the x-axis for clarity.