Abundance ratios [X_α/ H] and [X_Fe/H] versus minimum mass of the most massive companion m_C sin i of α-elements (top-left panel) and iron-peak elements (top-right panel), for stars with small planets (black empty triangles), with giant planets (red empty triangles), with confirmed BD companions (blue filled circles). The average values are shown as violet three-dotted-dashed lines. Lower panels show the mean abundances of stars with small and giant planets, and confirmed BD companions, in equal-sized bins appropriated for the logarithmic scale of companion masses as in Fig. B.4. Error bars represents the standard deviation of the mean divided by the square root of the number of stars in each bin. The green solid line depicts the parabolic fit of the data, whereas the violet three-dotted-dashed lines show the zero-order fits.