  We compare experimental resistivity data on Ga_{1-x}Mn_xAs films with
theoretical calculations using a scaling theory for strongly disordered
ferromagnets. All characteristic features of the temperature dependence of the
resistivity can be quantitatively understood through this approach as
originating from the close vicinity of the metal-insulator transition. In
particular, we find that the magnetic field induced changes in resistance
cannot be explained within a mean-field treatment of the magnetic state, and
that accounting for thermal fluctuations is crucial for a quantitative
analysis. Similarly, while the non-interacting scaling theory is in reasonable
agreement with the data, we find clear evidence in favor of interaction effects
at low temperatures.
