Cosmological parameter space, where the colour in the upper panels indicates the χ² corresponding to the adapted filter and in the lower panels to . The χ² of the left-hand side are determined with the cosmo-SLICS data and on the right-hand side with the flexible Gaussian process regression emulator. The grey cross marks the fiducial cosmology. One should not compare the right-hand side with the left-hand side directly, since in each node on the left, all four cosmological parameters are varied, whereas on the right, only two of the parameters are varied and the other two are fixed to the fiducial cosmology.