CELLULAR-AUTOMATON MODELS AND TRAFFIC FLOW

A recently introduced cellular automaton model for the description of traffic flow is investigated. It generalizes alpha-symmetric exclusion models which have attracted a lot of interest in the past. We calculate the so-called fundamental diagram (flow versus density) for parallel dynamics using in improved mean-field approximation which takes into account short-range correlations. For maximum velocity we find that the simplest of these non-trivial approximations gives the exact result. For higher velocities our results are in excellent agreement with numerical data.