For the inner few kiloparsecs of the elliptical galaxies, the velocity dispersion = 220 × (L / L *) 0.25, where L * is a characteristic galaxy luminosity (around 10 billion solar luminosities). (astronomynotes.com)
[Sukanya Chakrabarti et al, Clustered Cepheid Variables 90 kiloparsec from the Galactic Center] Dwarf galaxies like this one are thought to contain more dark matter than regular matter. (scientificamerican.com)
An elliptical galaxy's luminosity can be found from the velocity dispersion of the stars in the central few kiloparsecs of the galaxy. (astronomynotes.com)