Evolutionary Game Theory Analysis of Strategic Interactions in the Nigerian Road Freight Market

The Nigerian road freight market exhibits strategic interdependencies among operators, regulators, and shippers that generate sub-optimal equilibria including unsafe overloading, fare undercutting, and regulatory non-compliance. This study applies evolutionary game theory to model and analyse these strategic interactions, aiming to identify intervention points that can shift the market toward safer and more efficient equilibria. The research constructs a series of evolutionary game models representing three dyadic interactions: the overloading game between freight operators and weighbridge enforcers, the quality-price signalling game between freight operators and shippers, and the licensing compliance game between small operators and transport unions. Model parameters are calibrated using primary data from surveys of 200 truck operators, 80 freight shippers, and 40 regulatory officers in Lagos, Kano, and Onitsha, and from published accident and enforcement records. Evolutionary stability analysis reveals that current regulatory enforcement parameters support a stable polymorphic equilibrium in which non-compliance persists alongside compliance, rather than the evolutionarily stable compliance equilibrium required for safety improvement. Simulation of enforcement intensity and penalty structure variations demonstrates that a minimum 40 percent increase in detection probability, combined with increased sanction severity, is required to shift the system toward a compliance-dominant equilibrium. The study makes original contributions by introducing evolutionary game theory as an analytical tool in Nigerian transport economics research and demonstrating its practical applicability to policy design in low-enforcement transport markets. Keywords: evolutionary game theory, road freight, strategic interaction, regulatory compliance, Nigeria.