Braess paradox in a network with stochastic dynamics and fixed strategies

Abstract

The Braess paradox can be observed in road networks used by selfish users. It describes the counterintuitive situation in which adding a new, per se faster, origin–destination connection to a road network results in increased travel times for all network users. We study the network as originally proposed by Braess but introduce microscopic particle dynamics based on the totally asymmetric exclusion process. In contrast to our previous work Bittihn and Schadschneider (2016), where routes were chosen randomly according to turning rates, here we study the case of drivers with fixed route choices. We find that travel time reduction due to the new road only happens at really low densities and Braess’ paradox dominates the largest part of the phase diagram. Furthermore, the domain wall phase observed in Bittihn and Schadschneider (2016) vanishes. In the present model gridlock states are observed in a large part of phase space. We conclude that the construction of a new road can often be very critical and should be considered carefully.