A Power Law for the Duration of High-Flow States in Heterogeneous Traffic Flows

TL;DR

This paper investigates the duration of high-flow traffic states in freeways, revealing a power law distribution with an exponent around 2, supported by empirical data and a theoretical model of heterogeneous traffic with overtaking.

Contribution

It demonstrates that high-flow state durations follow a power law distribution with a consistent exponent, supported by empirical analysis and a novel theoretical model.

Findings

High-flow durations follow a power law with exponent ~2.

Empirical data aligns well with the theoretical model.

Heterogeneous traffic with overtaking explains the power law behavior.

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 is approximately 2, in dependently of the chosen flow threshold. In order to explain 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.