基于热点探测的城市区域公交可达性研究

提出基于出租车轨迹数据挖掘的城市区域公交可达性评估优化方法. 利用核密度分析和热点探测，识别出租车用户出行敏感区并用出行热度表征区域用户需求，研究敏感区域公交可达性. 从影响阻抗大小的指标出发定义公交可达性，选取影响可达性的关键指标描述阻抗，以各指标与热点值之间的相关性为权重获取公交可达性计算公式. 引入区域公交供需变异系数指标，供需莫兰散点图及区域公交供需差分布图，评价整个城市及热点区域的公交可达性供需情况，识别区域不平衡程度协助公交系统优化供给. 以西安市为例进行分析，结果表明：其区域公交供需的变异系数为1.89，存在一定的不平衡性；根据供需差及散点图的分布规律，识别出优先处理敏感区，采取措施提高其可达性对优化整个城市匹配度最为有效.

Bus Accessibility in Urban Areas Based on Hot Spot Detection

An evaluation method was proposed for bus accessibility in urban areas based on taxi trajectory data. First, kernel density analysis and hot spot detection were used to identify the travel sensitive areas of taxi users, and the travel heat was represented as the travel demand in the different areas for studying the public transport accessibility in the sensitive areas. Secondly, key indicators affecting accessibility were selected to model for evaluating bus accessibility by regarding the correlation between each indicator and the heat of hotspot as the weight index. Finally, the variation coefficient of public transport supply and demand, the Moran scatter map of supply and demand, as well as the distribution figure of the gap between public transport supply and demand, were introduced to evaluate the coupling between supply and demand of public transport accessibility for the whole city and identify the regional imbalance degree in order to help the public transport system optimize the supply of bus. Xi'an, a large city was selected as a case study for methodology verification. The variation coefficient of regional bus supply and demand is 1.89, which indicated that there is a certain imbalance. According to the distribution of the gap between supply and demand as well as scatter plot, it is effective to identify the priority-processing areas and take actions to improve the accessibility of them to optimize the coupling degree for the whole city.