Routing Games in the Wild: Efficiency, Equilibration and Regret (Large-Scale Field Experiments in Singapore)

TL;DR

This study analyzes real-world traffic routing in Singapore to assess if traffic equilibrates, aligns with latency minimization, and evaluates system efficiency using a new metric, revealing insights into practical traffic behavior.

Contribution

It introduces the 'stress of catastrophe' metric to measure combined inefficiencies in real-world traffic routing, bridging theory and practice.

Findings

Traffic tends to equilibrate over time.

System behavior partially aligns with latency minimization.

The new metric reveals significant inefficiencies in traffic routing.

Abstract

Routing games are amongst the most well studied domains of game theory. How relevant are these pen-and-paper calculations to understanding the reality of everyday traffic routing? We focus on a semantically rich dataset that captures detailed information about the daily behavior of thousands of Singaporean commuters and examine the following basic questions: (i) Does the traffic equilibrate? (ii) Is the system behavior consistent with latency minimizing agents? (iii) Is the resulting system efficient? In order to capture the efficiency of the traffic network in a way that agrees with our everyday intuition we introduce a new metric, the stress of catastrophe, which reflects the combined inefficiencies of both tragedy of the commons as well as price of anarchy effects.