Av (nebular) as a function of Hα radius. Symbol code is the same as in previous figures. The histograms for the local and high-z samples are normalized to the total number of objects in each sample. For the high-z samples, Av were obtained from the literature SED fittings to global magnitudes, transformed to Av(nebular) following Calzetti et al. (2000) (i.e. Av(nebular) = Av(SED)/0.44). For the local sample, Av values were derived from the Balmer decrement within apertures of about 1–3 kpc (see GM09, RZ11).