TRUSTS: Scheduling Randomized Patrols for Fare Inspection in Transit Systems Using Game Theory

Abstract

In proof‐of‐payment transit systems, passengers are legally required to purchase tickets before entering but are not physically forced to do so. Instead, patrol units move about the transit system, inspecting the tickets of passengers, who face fines if caught fare evading. The deterrence of fare evasion depends on the unpredictability and effectiveness of the patrols. In this article, we present TRUSTS, an application for scheduling randomized patrols for fare inspection in transit systems. TRUSTS models the problem of computing patrol strategies as a leader‐follower Stackelberg game where the objective is to deter fare evasion and hence maximize revenue. This problem differs from previously studied Stackelberg settings in that the leader strategies must satisfy massive temporal and spatial constraints; moreover, unlike in these counterterrorism‐motivated Stackelberg applications, a large fraction of the ridership might realistically consider fare evasion, and so the number of followers is potentially huge. A third key novelty in our work is deliberate simplification of leader strategies to make patrols easier to execute. We present an efficient algorithm for computing such patrol strategies and present experimental results using real‐world ridership data from the Los Angeles Metro Rail system. The Los Angeles County Sheriff's Department is currently carrying out trials of TRUSTS.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 01, 2012
Source ID
10.1609/aimag.v33i4.2432

Entities

People

  • Albert Xin Jiang
  • Christopher Kiekintveld
  • John P. Sullivan
  • Kevin Leyton‐brown
  • Milind Tambe
  • Tuomas Sandholm
  • Zhengyu Yin

Organizations

  • National Science Foundation
  • Natural Sciences and Engineering Research Council

Tags

Readers

  • Aviation Safety and Air Traffic Management
  • Maritime Security/Maritime Homeland Security
  • Strategic Security Studies