extinction, and half to synchrotron contamination in the quasars. However, their sample includes a significant number of steep-spectrum compact and super-luminal quasars. They also assumed a spherically symmetric dust model, which is likely to be inadequate.

We assume that the quasars and radio galaxies follow the same intrinsic relation between $\nu L_{\rm{\nu}}$(8  rest) \[W\] and L(\[OIII\]$\lambda5007$) \[W\], derived from the quasar points in Fig. 1 of Haas et al. (2008) using eqn. (6) to convert from L(151 MHz) to L(\[OIII\]$\lambda5007$). We assume:

$$\rm{log \nu L_{\rm{\nu}} (8~\micron~rest)} = 3.3 + 
0.9569\rm{log L([OIII]\lambda5007}).$$

No intrinsic scatter is assumed on this, as the scatter in eqn. (6) can reproduce the scatter in Fig. 1 of Haas et al. (2008). Using this normalisation, we assign the quasars randomly to one of the three type I quasar templates from Polletta et al. (2007). The radio galaxies are also assigned one of these template SEDs in an analogous manner, and then extinction of $A_{\rm{V}}$=0–40 mag is applied. An elliptical host galaxy model from the GRASIL library is assigned as for the FRIs but in this case normalised using the K–z relation of Willott et al. (2003) with an additional offset of $\Delta K = -0.36(\rm{log L(151 