Effective radius as a function of stellar mass for different galaxy samples. The samples include cEs (circles), LRDs from Maiolino et al. (2024) (diamonds), and LRDs with their size and stellar mass adopted from Labbe et al. (2025), and their black hole mass adopted from Greene et al. (2024) (squares). The color of each data point represents the black hole mass as indicated by the color bar. The solid black line shows the relation established by Shen et al. (2003) for local galaxies.