Twenty-nine RPs from the k-means clustering of the Hβ line that are identified as a signature of EB. The black lines show RPs, whereas shaded colored areas represent the density distribution of Hβ spectra within a cluster; darker shades indicate a higher density. Within a particular cluster, the Hβ profile that is farthest (measured in euclidean distance) from the corresponding RPs is shown by the black dotted line. As reference, the average quiet Sun profile (gray line) is plotted in each panel. RPs 0–24 show the typical EB-like Hβ profiles, that is, enhanced wings and unaffected line core, while RPs 25–28 display both an enhancement in the wings as well as in the line core. The parameter n represents the number of pixels in a cluster as percentage of the total of ∼1.73 × 10⁶ pixels.