Results of linear discriminant analysis (LDA). Upper panel: pre-defined boundary between the two clusters (red and blue points) is shown with dashed lines on the T_eff −FIP-bias diagram. The larger circles indicate the clusters assigned by the LDA. The three misclassified stars are ι Hor, HR 7291, and AY Cet. Lower panel: absolute value of the LD components corresponding to the given parameters. Thin lines come from bootstrap resampling, and error bars indicate the region between the 16th and 84th percentiles.