Distribution functions for the Gaussian models for four values of the dispersion of the V_M direction about V_M0. The dispersion of angles in the models is parametrized by the value of f_M (σ_M). It is the strongest in the purple case, f_M = 1.5 (σ_M = 38°). The other curves correspond to f_M = 1.2 (σ_M = 33°) in magenta, f_M = 1.0 (σ_M = 29°) in red, and the weakest, f_M = 0.5 (σ_M = 15°), in green. Each DF is computed over the same set of pixels used for the data analysis. The plot shows the results for the index of the power spectrum −1.5.