Joint and marginalised posterior plot of two correlated sources (~4″ apart) in the simulated 250 μm maps. Note that the joint and marginalised posteriors have been scaled by a factor of two using Eq. (6). The dashed black lines and the black cross indicate the fluxes extracted by XID+. The solid blue lines and the blue diamond indicate the true fluxes. The vertical dotted lines correspond to the 16th–84th percentiles in the posterior.