Pie charts for each spectral type that was used as input to the simulation (Ia-normal, 91T, 91bg, Ibc, Ic, Ic-BL, and IIP) and showing how these were typed by the human classifiers. The total number of simulated spectra per spectral type is indicated above the pie charts. All percentages have been rounded to the closest integer. In addition to the seven input types, the following classifications were allowed: Ia-CSM, IInS, and IIn (see Sect. 3). The grey colour corresponds to a few SNe that were classified as “none”. The recovery rate is higher among bright SNe. Fainter sub-types are more often classified as SNe IIn (including IInS). See text for more details.