  In this work we quantify the degree to which star-forming events are clumped.
We apply a precise and accurate technique to calculate the correlation
dimension Dc of the distribution of HII regions in a sample of disk galaxies.
Our reliable results are distributed in the range 1.5<Dc<2.0. We get
significant variations in the fractal dimension among galaxies, contrary to a
universal picture sometimes claimed in literature. The faintest galaxies tend
to distribute their HII regions in more clustered (less uniform) patterns.
Moreover, the fractal dimension for the brightest HII regions within the same
galaxy seems to be smaller than for the faintest ones suggesting some kind of
evolutionary effect.
