  In this paper, we study a routing and travel-mode choice problem for mobility
systems with a multimodal transportation network as a ``mobility game" with
coupled action sets. We develop a game-theoretic framework to study the impact
on efficiency of the travelers' behavioral decision-making. In our framework,
we introduce a mobility ``pricing mechanism," in which we model traffic
congestion using linear cost functions while also considering the waiting times
at different transport hubs. We show that the travelers' selfish actions lead
to a pure-strategy Nash equilibrium. We then perform a Price of Anarchy
analysis to establish that the mobility system's inefficiencies remain
relatively low as the number of travelers increases. We deviate from the
standard game-theoretic analysis of decision-making by extending our modeling
framework to capture the subjective behavior of travelers using prospect
theory. Finally, we provide a simulation study as a proof of concept for our
proposed mobility game.
