Estimating freeway origin-destination patterns using automation traffic counts

The origin-destination (O-D) flow of traffic vehicles are estimated using information provided by freeway surveillance and control systems. A nonlinear least squares (NLS) estimator that eliminated model specification error was introduced, and it performed well in terms of statistical efficiency and lack bias. This implies that accurate O-D estimation may require an accurate traffic flow model and that actual implementation may require joint estimation of O-D patterns and traffic flow model parameters.