Moreover, in industrialized countries a big part of the Gross National Product is absorbed by transportation. Traffic is also one of the biggest sources of air pollution. The amount of traffic in the EC is still increasing. New estimates indicate that it will have doubled till 2010. So it seems to be necessary to avoid, shift and optimize traffic.
Traffic shows some characteristics of a complex system.
There are stable and unstable states, deterministic, chaotic or even stochastic behaviour with phase transitions, fractal dimensions and self-organized criticality. In handling such a complex system, simulation can be a good tool. In the global warming debate, political decisions reckon on computer simulations. Likewise, computer models can be used to simulate the influence of governmental measures like road-pricing or building of new streets.