Impact of including different observations in a mock circular binary. Posteriors on the natal kick (v_k) and mass loss (Δm₂) are shown for when the various observational categories are included. Observational categories include spectroscopy (S), resolved astrometric orbit (O), and constraints on any of radial velocity (V_R), transverse velocities (V_T), or all three velocity components (V₃). All categories include spectroscopy (see Sect. 3.1 for justification). Categories without (with) the astrometric orbit are shown on the left (right). Colors correspond to differences in the available velocity constraints: when there are no velocity constraints (S, SO: dark green), when only the RVs are constrained (SV_R, SOV_R: blue), when only the transverse velocities are constrained (SV_T, SOV_T: yellow), and when there are measurements in all three directions (SV₃, SOV₃: red). All results here apply for the circular mock system; the results for the eccentric mock system are shown in Fig. B.1. Black dashed lines show the true values. Contours capture the 90% confidence interval of the 2D distributions. (a) Initially circular binary, without a resolved orbit. (b) Initially circular binary, with a resolved orbit.