基于SB分布的Mixed Logit交通方式分担模型及其验证

研究了SB分布函数的分布特性,发现SB分布比正态分布和对数正态分布能更好地表达单向偏好因子的参数,结合合肥市居民出行调查数据,建立了Logit交通方式分担模型和两种约束条件的SB分布Mixed Logit交通方式分担模型MIXED1和MIXED2,通过对比分析发现MIXED2模型对原始数据解释更合理,且更能体现出行者对出行时间认识上的差异性,文章最后对模型进行了公交出行时间敏感性测试,结果表明实施公交优先后,公交客流转移量主要来源于自行车使用者。基于SB分布Mixed Logit模型不存在Logit模型的IIA缺陷,且能体现出行者对影响因素认识上的差异性,其更适合于交通方式分担建模。

Mixed Logit Traffic Mode Split Model Based on SB Distribution and its Validation

The properties of SB distribution is analyzed fisrt and it is found that SB distribution which are bounded on both sides can describe uniform preference factors better than normal and log-normal distribution.Based on the residents' daily travel survey of Hefei city,a logit model and two SB distribution mixed logit modes(MIXED1 and MIXED2) with different restriction condition are established for traffic mode split of a certain area.The results indicate that MIXED2 is more fitable to explain the original data and more reasonable to describe uniform preference factors such as travel time.The sensitivity of the mixed logit model to transit travel time factor is also discussed,and the results show that the implementation of bus priority policy makes the bus passenger flow share increasing from the bike users.Furthermore,mixed logit model is more reasonable to model traffic mode split due to its reasonable to describe uniform preference factors and no possession of IIA limitation.