  Causal Dynamical Triangulations is a background independent approach to
quantum gravity. In this paper we introduce a phenomenological transfer matrix
model, where at each time step a reduced set of quantum states is used. The
states are solely characterized by the discretized spatial volume. Using Monte
Carlo simulations we determine the effective transfer matrix elements and
extract the effective action for the scale factor. In this framework no degrees
of freedom are frozen, however, the obtained action agrees with the
minisuperspace model.
