An integrated model for estimating time-varying network origin-destination distributions

This paper presents an integrated method for estimating time-varying O-Ds in urban networks. The proposed method starts with our previously developed two-stage, non-assignment-based model that can yield a time-varying O-Ds without a reliable prior O-D set and a dynamic traffic assignment model (DTA). With the initial estimated O-D set, one can compute the link-incident matrix with any acceptable DTA model and generate a revised distribution of network O-Ds. To further improve the estimation accuracy and also account for the impact of urban signals, we have developed an intersection O-D estimation model that can produce an additional set of system observation constraints based on either existing or estimated intersection turning fractions. Although the statistical properties and variances of such a system under a large-scale network remain to be investigated, the results of simulation experiments have clearly indicated that our proposed method for integrated estimation of time-varying network O-D distributions is quite promising. (C) 1999 Elsevier Science Ltd. All rights reserved.