Observed-link-flow-based OD matrix estimation with stochastic factors

A new iterative procedure with the consideration of the integrating stochastic factors is established for estimating origin-destination matrices. The analytical form of the link choice proportions has been developed, By minimizing the squared errors between estimated and observed link flows, the mathematical model balances all degrees of approximation for restricted equations, the recursive least squares method is conducted to evaluate OD matrices based on estimating theory. The conducted method is more receptive to the fluctuations in the observation due to integrating stochastic disturbances including measurement errors and temporal variations of the observed link flows, and can make better use of traffic information from observation systems. The analysis and simulation study show that the method is feasible. Then the factors of influencing compute results of OD matrices are discussed and some researches to be taken in the future are proposed.