The Prevalence of Paradoxes in Transportation Equilibrium Problems

Consider a congested transportation network, where the cost along each arc consists of a fixed cost plus a variable cost proportional to the flow. We present a new paradox demonstrating that, in a congested transportation network, a sufficiently high increase in the congestion effect along a route can result in the abandonment of a different route having the same origin and destination while the original route continues to be used.