城市交通出行方式选择的随机弹性分析

摘要

影响城市交通出行方式选择的因素有很多,本文致力于分析具有随机特性的因素对出行方式选择的影响程度,即随机弹性.使用具有较好收敛性的集计交通战略STM模型作为分析出行方式选择的工具,并根据对道路实测数据的统计分析,验证了作为影响出行方式选择的重要因素——小汽车出行速度为随机变量并服从k阶爱尔朗分布.根据经济学的随机弹性理论,推导出小汽车出行速度对出行方式选择的随机弹性计算模型,利用北京市的实际数据验证了模型的有效性.并得出结论:交通政策指标(影响因素)的可靠度越高,政策目标对政策指标的弹性值越稳定、集中,即政策目标达到的可靠度越高,随机弹性分析模型可作为一种交通政策量化分析的工具.%Among the factors that impact on urban travel mode choice, the ones with random distribution isrnthe main focus of this paper. The aggregate strategy traffic model ( STM) is used for model choice analysis.rnWith the field data, the car's travel speed is observed to be a random variable following the k-step Erlangrndistribution. Based on the random elasticity concept in economic theory, the elasticity calculation model ofrncar travel speed on the travel mode choice is developed. The model is validated by the field data of Beijingrncity. The results indicate that the higher the reliability of transport policy indicator (influencing factor) is,rnthe random elasticity becomes more steady and concentrated, and the policy target is more reliable to bernrealized.