Eur. Phys. J. B 68, 577-586 (2009)
https://doi.org/10.1140/epjb/e2009-00092-8

A power law for the duration of high-flow states and its interpretation from a heterogeneous traffic flow perspective

¹ ETH Zurich, UNO D11, Universitätstr. 41, 8092 Zurich, Switzerland
² II. Institut für Theoretische Physik, Pfaffenwaldring 57, 70550 Stuttgart, Germany

Corresponding author: ^a dhelbing@ethz.ch

Received: 19 June 2008
Revised: 17 December 2008
Published online: 14 March 2009

Abstract

We study the duration of “high-flow states” in freeway traffic, defined as the time periods for which traffic flows exceed a given flow threshold. Our empirical data are surprisingly well represented by a power law. Moreover, the power law exponent for a two-lane freeway seems to be independent of the chosen flow threshold. In order to interpret this discovery, we investigate a simple theoretical model of heterogeneous traffic with overtaking maneuvers, which is able to reproduce both, the empirical power law and its exponent.