1D marginalized posterior PDFs of the K2-18b and c semi-amplitudes from analyses of the full HARPS (blue), the reduced CARMENES (red), and their joint (black) RV time-series. The dashed vertical lines and shaded regions depict the maximum a posteriori values and 1σ confidence intervals respectively. All K_b and K_c values are consistent at the 1σ level which is approximated by each PDF’s 16th and 84th percentiles.