This study investigates various methods for autonomous traffic signal control. We look into different types of control methods, including fixed time, adaptive, analytic, and reinforcement learning approaches. Machine learning approaches are compared with the “analytic” approach, which is used as “gold standard” for performance assessment.

We find that conventional machine learning approaches are better than the analytic approach, but require a lot more computer power. We, therefore, introduce a novel hybrid method called “analytically guided reinforcement learning” or shorter “ α -RL”. This approach is implemented in our “GuidedLight agent” and tends to outperform both, classical machine learning and the analytic approach, while largely improving convergence.

This method is therefore suited as a “green IT” solution that improves environmental impact in a two-fold way: by reducing (i) traffic congestion and (ii) the processing power needed for the learning and operation of the traffic light control algorithm.

M. Korecki, D. Helbing, Analytically Guided Reinforcement Learning for Green It and Fluent Traffic, IEEE Access 10 (2022).