The Two-Mode Problem: Second-Best Pricing and Capacity

Suppose that there are two congestible modes of travel from A to B - road and rail for concreteness - which are imperfect substitutes in demand. Road congestion from A to B is underpriced; this is an unalterable distortion. Compared to the first best, should the transportation planner choose a wider or narrower road, raise or lower the rail fare, and expand or contract rail capacity? This paper provides a synthetic review of the literature on the problem, presents some new results, and discusses directions for future research on this and related second-best problems.second-best, pricing, investement, road, rail