Outputs of the three models presented in Fig. 3, used to infer the likelihood term ℒ_scatter. From top to bottom, the models have coherence lengths of 1, 4, and 10 kpc. Left: model EW distributions as a function of R′, with the black curve showing the relation of Eq. (2). Downward arrows show spaxels whose predicted EWs are below the detection limit of 0.2 Å and are therefore classified as “model nondetections”. Right: distributions of the differences between the EW values and the corresponding values predicted by Eq. (2), for data (blue) and models (red).