Distribution of the T_eff residuals (Priam minus literature) normalized by their combined uncertainties for the test data set, for different Galactic latitudes (left column) and longitudes (right column). The Priam uncertainty σ_Priam used in the computation for each star is formed from the lower uncertainty level if T_eff,Priam > T_eff,lit, and from the upper uncertainty level otherwise. The upper left corner of each panel reports the mean μ and standard deviation (σ) of these normalized residuals. The red curves are unit Gaussian distributions. The vertical lines indicate the median of each distribution. For unbiased estimates and correct uncertainties in both the literature and our work, the histograms and the red Gaussians should match.