Diagnostics for the model trained on the ideal GUMS solar neighbourhood sample, using only the Gaia optical photometryand 5D phase-space information. Left panel: velocity distribution in Cartesian coordinates, assuming v_los = 0 km s⁻¹. Right panel: HR diagram. The blue points mark the true positive (correctly identified halo stars), the orange points mark the false negatives, while the red squares mark the false positives. Not knowing the line-of-sight velocities of the test stars makes for an increase in the numbers of false negative detections.