摘要
城市网约车订单需求体现了居民出行活力,同时表征了出行规律和内在特征。如何从复杂动态的时变数据中准确地识别异常点并进行调度优化,是优化网约车平台运力的关键环节。建立了网约车订单需求数据的时间序列图,并分析了订单需求的动态特性,提出1种基于混合机器学习框架的网约车订单需求预测模型(ARIMA-BPNN-DSR,ABD)。混合模型由差分整合移动平均自回归模型(auto regressive integrated moving average model,ARIMA)和反向传播神经网络(back propagation neural network,BPNN)通过动态选择回归算法(dynamic selection of regression,DSR)融合而成。混合模型汲取了统计方法的鲁棒性和机器学习方法的高效性,并考虑各个独立基线模型在数据局部空间上的性能表现。以2019年和2020年(疫情影响下)厦门市滴滴网约车平台订单数据作为试验基准并进行对比分析,结果表明:①与多个基线模型相比,ABD模型实现了最优的预测性能,同时在面向疫情外部因素影响下同样表现出优异的性能;②消融实验表明,在常规序列中,BPNN对融合模型的预测性能增益更高。混合模型相比较单独的ARIMA和BPNN模型,在预测性能指标上,平均绝对误差(mean absolute error,MAE)分别提高22.77%和13.50%,均方百分比误差(mean absolute percentage error,MAPE指标分别提高21.71%和12.37%。另外,在受到2020年的外部干扰下,ARIMA提供的稳定性至关重要;③预测结果与观测值之间的残差结合3-sigma异常检测准则实现订单数据中的需求突增异常点自动识别,以此提高交通管理效率。该结果说明,提出的ABD模型具有良好的预测精度和鲁棒性。
The demand for urban ride-hailing services holds significant potential for understanding residents'travel behaviors,patterns and intrinsic characteristics.Accurately identifying anomalies and optimizing scheduling from the complex and dynamic spatio-temporal data of ride-hailing usage can contribute to extending a platform's capacity.Time series graph of ride-hailing order data is established to analyze its dynamic characteristics.Therefore,a hybrid prediction model that predicts ride-hailing order demand based on machine learning methods,called ARIMA-BPNN-DSR(ABD),is proposed by integrating the auto regressive integrated moving average model(ARIMA)and the back propagation neural network(BPNN)modules.To achieve the hybrid prediction model,the dynamic selection of regression(DSR)method is applied to fuse these two modules.The DSR method takes advantage of the robustness of statistical methods and the efficiency of machine learning methods,and considers the performance of independent models within the local data space.Extensive experiments and analyses are conducted on the time series data from Didi's ride-hailing order demand in Xiamen City,including data from 2019(without epidemic)and data from 2020(with epidemic).Experimental results show that:①The ABD model outperforms baseline models,providing accurate predictions for peak demand.Therefore,incorporating ensemble learning strategies significantly improves the prediction accuracy of the proposed model.②Ablation experiments reveal that the BPNN significantly enhances the predictive performance of the fusion model in standard sequences.Compared to individual ARIMA and BPNN models,the mean absolute error(MAE)of ABD model is reduced by 22.77%and 13.50%,and the mean absolute percentage error(MAPE)is reduced by 21.71%and 12.37%,respectively.Considering the external interference in 2020,the stability provided by ARIMA is essential.③By comparing the error between historical data and predicted results with the 3-sigma anomaly detection criteria,ABD model accurately identifies anomalies in the order data,thereby increasing the efficiency of traffic management.In conclusion,the proposed ABD model has a better performance in both accuracy and robustness.
作者
李之红
申天宇
文琰杰
许旺土
LI Zhihong;SHEN Tianyu;WEN Yanjie;XU Wangtu(School of Civil and Transportation Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;School of Traffic and Transportation Engineering,Central South University,Changsha 410075,China;School of Architecture and Civil Engineering,Xiamen University,Xiamen 361005,China)
出处
《交通信息与安全》
CSCD
北大核心
2023年第3期157-165,174,共10页
Journal of Transport Information and Safety
基金
国家社会科学基金项目(21FGLB014)资助。
关键词
智能交通
订单需求预测
混合机器学习框架
异常点识别
网约车
Intelligent transportation
Order demand prediction
Hybrid machine learning framework
Anomaly detection
Online car-hailing
