Optimal strategies: A new assignment model for transit networks

The authors describe a model for the transit assignment problem with a fixed set of transit lines. The traveler chooses the strategy that allows him or her to reach his or her destination at minimum expected cost. First the authors consider the case in which no congestion effects occur. For the special case in which the waiting time at a stop depends only on the combined frequency, the problem is formulated as a linear programming problem of a size that increases linearly with the network size. A label-setting algorithm is developed that solves the latter problem in polynomial time. Nonlinear cost extensions of the model are considered as well.