The radio-NIR ratio as a function of redshift for different galaxy templates (solid and dashed lines). The dotted lines are the radio-NIR ratios of our sample. The radio flux density of the optically faint radio sources pertains to the total FIRST radio flux density, from the sum of the integrated power of all the FIRST components (Table 1) and the NIR emission pertains to the central NIR component, which is coincident with the center of the radio structure (components N; Table 3). The NIR magnitude system is Vega. The large dots are the median redshift values for the 3CR (dashed; Spinrad 1985) and GPS (solid; Labiano et al. 2007) sample sources, with a one σ errorbar.