Comparison of our theoretical WDLFs constructed under the assumption of different values of μ₁₂ with the unified WDLF constructed merging the WDLFs derived by Harris et al. (2006), Krzesinski et al. (2009), and Rowell & Hambly (2011). Red error bars correspond to those derived as σ_i = Max [σ_i,Uni,σ_i,SSS,σ_i,SDSS]. See Sect. 4 for details. The inset shows the value of the χ² per degree of freedom ν of the χ²-test for the two different sets of error bars. Gray areas indicate the magnitude ranges used for the χ²-test (3 < M_Bol < 9) and for the normalization procedure (10 < M_Bol < 13).