Sensitivity indices for the second series of 1600 galform uns, varying seven model parameters (Table 2), computed using the coarse two-bin description of the luminosity function. The bar colours indicate the values of different indices, the first index (equation 11) (S₁, red) and total-order index (equation 15) (S_T, blue) for each parameter. The left-hand panel shows indices for galaxies in the luminosity bin fainter than L*, and the right-hand panel for galaxies in the bin brighter than L* (equation 19). The black bars show the 1σ confidence intervals for the sensitivity indices.