路径流量唯一性实证研究

Empirical Study on the Uniqueness of Route Flow

传统静态交通分配方法无法获得稳定且唯一的路径流量解,解决该问题的一个方法是使用比例一致性条件。如果该条件能在实际路网中被证实(近似)成立,可为该条件的应用扫清理论上的障碍,从根本上解决基于路径流量分析结果中广泛存在的不唯一性问题。利用广东省高速公路路网数据,对符合比例一致性条件的路径对流量,基于最小二乘法构造特定的F统计量进行F检验,并通过诊断分析排除异常值的干扰。结果显示:对广东省高速公路路网中符合条件的路径对流量分3种情况进行分析验证,得到相应的F观测值分别为5 995.601 2,1 324.274 7和699.549 4。这表明在显著性水平为0.05的情况下,均能通过F检验,即比例一致性条件在实际路网上是存在的。

Traditional static traffic assignment methods have difficulties in achieving stable and unique route flow solution,a potential solution to this problem is adding proportionality condition. If the existence of this condition could be proved in real traffic network,it can clear theoretical obstacles for its application and basically solve the situation of broadly route flow un-uniqueness. By using the proportionality qualified pairs of route flows from Guangdong expressway network data,we conducted F-test by the constructed specific statistics F based on least square method. In addition,we implemented diagnostic analysis to exclude the influence of the outliers. The result indicates that when testing the qualified route pairs of Guangdong expressway network under 3 cases,the relative observed value of F is 5 995. 601 2,1 324. 274 7 and699. 549 4,which can pass the F-test easily at significance level 0. 05,showing that the proportionality condition exists in the actual network.