Top panel: radial velocities for the two components of the pair HIP 473 AB = WDS 00057+4549AB. Dots refer to CORAVEL velocities and triangles to velocities from Tokovinin & Smekhov (2002) or Chubak et al. (2012) for the last point, with the time spanned by the measurements represented by the horizontal bar. Open symbols refer to component A and filled symbols to component B. The parallel dashed lines are just a guide to the eye. Bottom panel: radial-velocity difference B-A, with their errors taken as the root-mean-square of the errors on A and B.