Sensitivity Analysis Of Backward OD Matrix Based On TransCAD

With the development of traffic information collection technology and the popularization of monitoring system,the access to traffic on the road network becomes more and more easy.Therefore,the method of estimating the flow of OD matrix through the observation of traffic is becoming more and more important.This paper first introduces the theory and method of OD matrix backstepping,and establishes the road network model with some specific urban road network in Suzhou.This paper introduces the sensitivity analysis method,analyzes the factors influencing the backstepping of OD matrix,and selects the main influencing factors: traffic distribution methods(user balance method and random user equilibrium method);BPR resistance function within ? and ?.The three sensitivity analysis and evaluation indexes are selected with the purpose of backstepping,including root mean square error,relative error and modal confidence criterion(MAC).Then,the sensitivity analysis of OD matrix backstepping results is carried out.The base OD matrix is obtained by calibrating ? and ?.Analyze the influencing factors by using the single factor sensitivity analysis method,the different OD matrixs and the distribution flow are obtained by changing the factors.The OD matrix and the reference OD matrix are compared by the evaluation indexes,the road distribution flow and road observation traffic are compared by the evaluation indexes.The results show that the random user balance method is more accurate than the user equilibrium method,and it is suggested to use the random user balance method in the reverse OD matrix and propose the range of ?and?.The research results can provide a reference for the better use of TransCAD software for OD matrix backstepping and improving backstepping accuracy.