AVSSs obtained for the compact AR 12381 with approach 1 (left panels) and approach 2 (right panels). Panels (a) and (b) panels show the AVSSs of the AR area, fluctuation spectra. Panels (c) and (d) present the AVSSs of the positive and negative magnetic flux fluctuation spectra. Panels (e) and (f) show the AVSSs of the signed and unsigned magnetic flux fluctuation spectra. In panels (a) and (b), the markers ’+’ and ’×’ indicate and , respectively; whereas marker ’*’ denotes (i.e. the combination of both polarities). In panels (c) and (d), the markers ’⋄’ and ’▫’ indicate , while the markers ’△’ and ’°’ are used for . In panels (e) and (f), markers ’⋄’ and ’▫’ show , while markers ’△’ and ’°’ denote , th ⊆ {350, 700, 900}. The colours of the markers correspond to the applied magnetic field thresholds: th = 350 G (black); th = 700 G (blue); th = 900 G (red). We note that for the sake of better visualisation, the markers in all plots are manually slightly shifted along the abscissa to avoid their overlapping.