Matías J M, Taboada J, Ordóñez C, Nieto P G
Statistics Department, Vigo University, Vigo, Spain.
J Hazard Mater. 2007 Aug 17;147(1-2):60-6. doi: 10.1016/j.jhazmat.2006.12.042. Epub 2006 Dec 21.
This article describes a methodology to model the degree of remedial action required to make short stretches of a roadway suitable for dangerous goods transport (DGT), particularly pollutant substances, using different variables associated with the characteristics of each segment. Thirty-one factors determining the impact of an accident on a particular stretch of road were identified and subdivided into two major groups: accident probability factors and accident severity factors. Given the number of factors determining the state of a particular road segment, the only viable statistical methods for implementing the model were machine learning techniques, such as multilayer perceptron networks (MLPs), classification trees (CARTs) and support vector machines (SVMs). The results produced by these techniques on a test sample were more favourable than those produced by traditional discriminant analysis, irrespective of whether dimensionality reduction techniques were applied. The best results were obtained using SVMs specifically adapted to ordinal data. This technique takes advantage of the ordinal information contained in the data without penalising the computational load. Furthermore, the technique permits the estimation of the utility function that is latent in expert knowledge.
本文介绍了一种方法,该方法使用与道路各路段特征相关的不同变量,对使短路段道路适合危险货物运输(特别是污染物)所需的补救措施程度进行建模。确定了31个决定事故对特定路段影响的因素,并将其细分为两个主要类别:事故概率因素和事故严重程度因素。鉴于决定特定路段状况的因素数量众多,实现该模型的唯一可行统计方法是机器学习技术,如多层感知器网络(MLP)、分类树(CART)和支持向量机(SVM)。无论是否应用降维技术,这些技术在测试样本上产生的结果都比传统判别分析产生的结果更有利。使用专门适用于有序数据的支持向量机获得了最佳结果。该技术利用了数据中包含的有序信息,而不会增加计算负担。此外,该技术允许估计专家知识中潜在的效用函数。