Upper panels: comparison of the ATHOS output for T _eff, [Fe/H], and log g with literature results for the ELODIE spectral library (version 3.1, Prugniel et al. 2007, see text for quality cuts made here). In case a star occurs with multiple spectra in the library, it is reflected by more than one point here. Dashed lines represent the one-to-one relation. The colors reflect the internal statistical uncertainties computed with ATHOS. Lower panels: residual distribution. All residuals are determined via Δx = x _lit − x _ATHOS.