  Recent measurements of the magnetoresistance (MR) of amorphous
superconducting thin films in tilted magnetic fields have displayed several
surprising experimental details, in particular a strong dependence of the MR on
field angle at low magnetic fields, which diminishes and then changes sign at
large fields. Using a generalized site-bond percolation model, that takes into
account both the orbital and Zeeman effects of the magnetic field, we show that
the resulting MR curves reproduce the main experimental features. Such
measurements, accompanied by the corresponding theory, may be crucial in
pinpointing the correct theory of the superconductor-insulator transition and
of the MR peak in thin disordered films.
