Relation between FUV–NUV color and IRX. The left panel shows the relation as a function of IRAS 60 μm luminosity, Liras 60 μm. The right panel is the same but with total IR luminosity, Ltir. Dots: galaxies with Lir < 1011 L⊙, crosses: galaxies with 1011 L⊙ ≤ Lir < 1012 L⊙, triangles: galaxies with Lir ≤ 1012 L⊙. Here, Lir stands for Liras 60 μm in the left panel and Ltir in the right panel. The solid curve in each panel represents the IRX–UV-color relation of UV-luminous starbursts (Takeuchi et al., 2012).