Formulating the within-day dynamic stochastic traffic assignment problem from a Bayesian perspective

• A new formulation for the dynamic stochastic traffic assignment problem.
• Treat route traffic packets as random variables.
• Acquire the probability distribution of the random variables.
• Estimate the characteristics of the probability distribution.

This study proposes a formulation of the within-day dynamic stochastic traffic assignment problem. Considering the stochastic nature of route choice behavior, we treat the solution to the assignment problem as the conditional joint distribution of route traffic, given that the network is in dynamic stochastic user equilibrium. We acquire the conditional joint probability distribution using Bayes’ theorem. A Metropolis–Hastings sampling scheme is developed to estimate the characteristics (e.g., mean and variance) of the route traffic. The proposed formulation has no special requirements for the traffic flow models and user behavior models, and so is easily implemented.