城市出租车出行轨迹网络的空间分异特征研究

Research on Spatial Differentiation Characteristics of Urban Taxi Trip Trajectory Network

城市居民的出行特征受到城市资源配置及其结构功能的影响。以北京市城六区为例,利用出租车全球定位系统(GPS)轨迹数据,构建出租车服务利润率模型和出租车出行轨迹网络模型,分析出租车出行轨迹网络的空间分异特征。研究发现,出租车出行轨迹网络的度累积分布服从幂律分布,是一个无标度网络。出租车的服务利润率和网络结构具有较强的关联性。出租车出行轨迹网络的出入度和服务利润率在时间上都具有明显的“早晚高峰”现象,这说明在早晚高峰时段,出租车的收益水平和供需数量都处于较高的状态。北京市出租车需求在城六区的地域分布极不平衡,区域之间存在较大差异。对出租车需求较大的行政区,司机的收益水平较低,反之则较高。对出租车需求较大的功能区,司机服务利润率处于较低水平。从服务利润率视角下分析出租车出行轨迹网络的空间分异特征,能够理解城市在服务利润率视角下居民对出租车的需求变动规律,有助于当局合理规划城市结构布局,优化城市交通资源配置,适度调控出租车保有量,进一步完善出租车市场利益分配格局具有一定的指导意义。

The characteristics of urban residents’travel are influenced by the resource allocation and structure function of the city.Taking the six districts in Beijing as the example,we use the GPS trajectory data of taxis,construct a model of service profit margin and taxi trip trajectory network to analyze the spatial differentiation characteristics of taxi trip trajectory network.Analysis result shows that,the taxi trip trajectory network is a scale-free network,whose cumulative degree distribution follows a power-law distribution.There is a strong correlation between service profit margin and network structure of taxi.In terms of time dimension,the in/out degree and service profit margin of the taxi trip trajectory network reflect an obvious morning and evening peak,indicating that the income level of the driver and the supply and demand of the taxi service are both higher in the peak time.The demand of taxi service varies greatly in the six districts in Beijing with a great gap among different areas.For administrative districts with a higher demand of the taxi service,the income level of the driver is lower,while for administrative districts with a lower demand,the income level of the driver is higher.For functional zones with a larger demand of the taxi,the service profit margin is in a lower level.By analyzing the spatial differentiation characteristics of taxi trip trajectory network from the perspective of service profit margin,the norm of the city’s demand change for taxis service can be mastered,which will help the local government better design the urban structure and layout,optimize the urban traffic resource allocation and adjust the number of the taxi,giving guidance to the development of the profit distribution pattern in the taxicab market.