滑动窗窗体长度及滑动步长对事故多发路段鉴别影响

The Impact of Window Size and Sliding Length on the Results of Black Spots Identification

以京珠高速公路粤北段的事故多发路段鉴别为案例,分析滑动窗口法鉴别事故多发路段时可能存在的问题,探讨滑动窗窗体长度和滑动步长对事故多发路段鉴别的影响,给出了运用分位数法确定最佳窗体长度及滑动步长的方法.研究结果表明:在不同滑动窗体长度和不同滑动步长下会出现不同的鉴别结果,若滑动窗体长度和滑动步长使用不恰当,会出现事故多发路段遗漏或夸大的情况;滑动窗窗体长度越长,累计事故多发路段越长;滑动步长越长,累计事故多发路段长度越短;滑动步长与窗体长度的比值在0.4~0.8时的组合最佳.

Taking Jingzhu freeway for example to identify the black spots,analyzing the potential issue of sliding window application,and discussing the impact of window size and sliding length on the results of black spots identification.Finally,a method is provided based on Quantile Method to choose the optimum window size and sliding length.The result shows that different size of window and sliding length decide the different result of black spots,if the window size and the sliding length is unseasonable or the method are used incorrectly,the results will be omitted or be exaggerated when use the sliding window identify the black spots.The longer the window size,the longer black spots be identified.The longer the sliding length,the less black spots be identified.It is optimum combination that the ratio of the sliding length to the window size is 0.4~0.8.