Histograms of the extinction-corrected flux ratios and UV colors of mass-selected objects assuming a Salpeter IMF. Top panel: histogram of log(F_Hα/f_λFUV). The green histogram shows the objects within the H I gas footprint, the blue histogram shows the objects outside it, and the orange histogram shows the star clusters associated with M 83. The orange histogram was obtained by scaling the blue histogram with the IN/OUT area ratio and subtracting it from the green histogram. The change in the flux ratio if is assumed to be larger by 0.1 mag is shown with a black arrow. Bottom panel: same as the top panel but for FUV−NUV. The shaded parts of the histograms correspond to the Hα-bright (log(F_Hα/f_λFUV) > 1) clusters and the blue (FUV−NUV < 0) clusters, respectively. These histograms illustrate the subtraction of background contamination from our cluster counts.