Distance accuracy and precision for the four input observable sets introduced in Sect. 2.4. Upper panels: distribution of relative distance errors, (d_BPG−d_true) /d_true, for the sample of simulated stars drawn from PARSEC models (see Fig. 1) with high-resolution-like observational errors (left; see Sect. 2.2) and low-resolution-like errors (right). In each panel, we use the distances based on the four sets of measured parameters listed in Sect. 2.4. The results for dwarfs are shown in black, the results for the giants in grey. Solid lines: set 1 (x = {[M/H] ,T_eff,log g,m,colours}); dashed lines: set 2 (x = {[M/H] ,T_eff,log g,m}); dash-dotted lines: set 3 (x = {[M/H] ,log g,m,colours}); dotted lines: set 4 (x = {[M/H] ,m,colours}, with a cut at | Δlog g | < 0.5 dex). Bottom panels: distributions of our relative (internal) distance uncertainties, σ(d_BPG) /d_BPG.