Radii as a function of orbital periods of the singles (magenta crosses) and multis (blue bullets) in the FGK sample, excluding hot Jupiters. The colour of each grid cell represents the percentage of planets that are singles within the cell, as indicated by the colour bar (see Table 3). The upper and the right panels display the empirical cumulative distribution functions of the orbital periods and planetary radii, respectively. The K–S test p-values indicate that the radii and orbital period distributions of the singles and multis are statistically indistinguishable.