Infrared excess (IRX) in the (NUV − r) versus (r − K) diagram. Left figure: volume-weighted mean IRX (⟨IRX⟩) for the 24  μm-selected sources in 4 redshift bins, color coded in a logarithmic scale (shown in the top right panel). We overplot in the top-left panel the attenuation vectors for starburst and SMC attenuation curves assuming E(B − V) = 0.4. In each panel, we overplot the vector NRK (black arrows) and its perpendicular lines (gray solid lines) corresponding to NRK in the range 0 to 4. (note the different dynamic ranges in x and y-axis warping the angles). Right figure: dispersion around the mean (σ(IRX)), color coded in a logarithmic scale.