Smoothed distribution of the companions in the semi-major axis a – mass ratio q plane. Top row: observed distribution. Middle row: detection completeness maps. Bottom row: observed distribution corrected for completeness. Left column gives results for the whole sample; the central column gives results from stars more massive than 3.5 M_⊙; the right column for less massive stars. The magenta area in the lower row marks the region with completeness < 0.2, not used in the analysis.