For billions of people around the world, road transportation is the most affordable and accessible means of getting around. Mobility is essential in modern society, enabling individuals to work, shop, attend educational institutions, and connect with family and friends. However, traffic congestion has become a major problem, particularly in today’s sprawling urban mega-cities. The high volume of people trying to travel from one place to another simultaneously leads to severe congestion. This issue has far-reaching consequences: it wastes valuable time, diminishes quality of life, increases fuel consumption and costs, contributes to higher emissions and noise pollution, and can negatively impact residents’ health.

Numerous solutions have been proposed in scientific literature to address traffic congestion, including infrastructural controls like signalized intersection management, ramp metering, and perimeter control, as well as economic instruments such as tolled roads, tolled lanes, and congestion pricing. While the effectiveness of these solutions is generally well-supported by the findings in the literature, they often encounter significant public resistance during real-world implementation. This opposition largely stems from concerns about fairness and equity.

In light of these challenges, I investigate the role of fairness in shaping more sustainable mobility solutions. My exploration unfolds in three key areas:

1. Defining Fairness: I examine how fairness can be quantitatively and objectively defined, focusing on concepts of distributive and procedural fairness as discussed in existing literature.
2. Designing Fair and Efficient Systems: I analyze how to design traffic control systems that balance fairness and efficiency, and explore whether these two goals are inherently at odds or can be harmonized.
3. Enhancing Economic Instruments: I look into ways to improve the design of economic tools, such as congestion pricing, to foster greater equity. This includes exploring alternatives to monetary incentives, like tradable credit schemes, rationing, and karma-based mechanisms, to address public criticism and encourage real-world adoption.

Relevant research questions in this context involve…

• What is fairness?
• Are fairness and efficiency conflicting goals?
• How can we allocate spatio-temporal resources in equitable societies?

Publications

• Kevin Riehl, Anastasios Kouvelas, Michail Makridis (2024). Towards fair roads–Why we should & how to improve the fairness in traffic engineering. Preprint in arXiv.
• Kevin Riehl, Anastasios Kouvelas, Michail Makridis (2024). Fair Money–Public Good Value Pricing With Karma Economies. Preprint in arXiv.
• Kevin Riehl, Anastasios Kouvelas, Michail Makridis (2024). Resource Allocation with Karma Mechanisms. Preprint in arXiv.
• Kevin Riehl, Anastasios Kouvelas, Michail Makridis (2024). Priority pass: Signal control with focus on needs. 24th Swiss Transport Research Conference (STRC 2024), Ascona, Switzerland, May 15-17, 2024.