The Price of Anarchy in Transportation Networks: Efficiency and Optimality Control

TL;DR

This paper investigates how uncoordinated driver behavior leads to inefficient traffic flow in city networks, quantifies the resulting social costs, and explores counterintuitive strategies like street closures to improve overall traffic conditions.

Contribution

It provides a simulation-based analysis of the price of anarchy in urban traffic networks and reveals paradoxical effects of traffic management strategies.

Findings

Uncoordinated drivers can waste significant travel time.

Blocking certain streets can improve traffic flow.

Complex network analysis suggests similar paradoxes in physics.

Abstract

Uncoordinated individuals in human society pursuing their personally optimal strategies do not always achieve the social optimum, the most beneficial state to the society as a whole. Instead, strategies form Nash equilibria which are often socially suboptimal. Society, therefore, has to pay a price of anarchy for the lack of coordination among its members. Here we assess this price of anarchy by analyzing the travel times in road networks of several major cities. Our simulation shows that uncoordinated drivers possibly waste a considerable amount of their travel time. Counterintuitively,simply blocking certain streets can partially improve the traffic conditions. We analyze various complex networks and discuss the possibility of similar paradoxes in physics.