Distribution of the dispersion from the individual best-fitting relations for of all regions combined (see text). The dispersion (in dex units, ) is computed as the distance of the individual values of M_dust and Maœ from the best-fit relation with M_⋆ (top and middle panels) or Mask (bottom panel), we include all objects with Μ_⋆ > 0.15 Μ_⊙. The solid black lines show the results when upper limits are treated as actual measurements, gray shaded areas show the results when they are excluded. The blue solid and dotted lines show the Gaussian fits to the two distributions.