Dimensional reduction in a model with infinitely many absorbing states

Using the Monte Carlo method, we study a two-dimensional model with infinit ely many absorbing states. Our estimation of the critical exponent beta sim ilar to 0.273(5) suggests that the model belongs to the (1+1) rather than t o (2+1) directed-percolation universality class. We also show that for a la rge class of absorbing states the dynamic Monte Carlo method leads to spuri ous dynamical transitions. [S1063-651X(99)50112-8].