Radius-luminosity relation for the Mg II BLR. The rest-frame time lag from reverberation mapping and the continuum luminosity at 3000 Å are from Yu et al. (2023, in blue) and Shen et al. (2024, in green). The fit from Yu et al. (2023) is superimposed as a continuous line. The BLR half-light radii measured from microlensing are superimposed in red. Squares show the measurements from this work. Diamonds show the measurements from Fian et al. (2023); Fian et al. (2024a) for Q0957+561 and J1004+4112.