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Studying travel-related individual assessments and desires by combining hierarchically structured ordinal variables 总被引:1,自引:1,他引:0
Ordinal measures are frequently encountered in travel behavior research. This paper presents a new method for combining them
when a hierarchical structure of the data can be presumed. This method is applied to study the subjective assessment of the
amount of travel by different transportation modes among a group of French clerical workers, along with the desire to increase
or decrease the use of such modes. Some advantages of this approach over traditional data reduction technique such as factor
analysis when applied to ordinal data are then illustrated. In this study, combining evidence from several variables sheds
light on the observed moderately negative relationship between the personal assessment of the amount of travel and the desire
to increase or decrease it, thus integrating previous partial (univariate) results. We find a latent demand for travel, thus
contributing to clarify the behavioral mechanisms behind the induced traffic phenomenon. Categorizing the above relationship
by transportation mode shows a desire for a less environmental-friendly mix of modes (i.e., a greater desire to use heavy
motorized modes and a lower desire to use two-wheeled modes), whenever the respondents do not feel to travel extensively.
This result, combined with previous theoretical investigations concerning the determinants of the desire to alter trips consumption
levels, shows the importance of making people aware of how much they travel.
Marco Diana is a permanent researcher working at the Department of Hydraulics, Transport and Civil Infrastructures of Politecnico di Torino, Italy. His research interests include the study of innovative forms of public transport services and the analysis of multimodality behaviors. Tingting Song is a Scientific Programmer at The Rockefeller University, Center for Clinical and Translational Science, Biostatistics, Epidemiology, and Research Design Core, New York, NY, USA. She works on algorithms for non-parametric methods and their applications in medical research. She maintains the muStat package on CRAN.r-project.org and the Web server on muStat.rockefeller.edu. Knut M. Wittkowski is a Senior Research Associate at The Rockefeller University and Head of Biostatistics, Epidemiology, and Research Design at its Center for Clinical and Translational Science, New York, NY, USA. His research focuses on methods, meta data, and user interfaces to integrate nonparametric statistics into research and decision support systems. 相似文献
Knut M. WittkowskiEmail: |
Marco Diana is a permanent researcher working at the Department of Hydraulics, Transport and Civil Infrastructures of Politecnico di Torino, Italy. His research interests include the study of innovative forms of public transport services and the analysis of multimodality behaviors. Tingting Song is a Scientific Programmer at The Rockefeller University, Center for Clinical and Translational Science, Biostatistics, Epidemiology, and Research Design Core, New York, NY, USA. She works on algorithms for non-parametric methods and their applications in medical research. She maintains the muStat package on CRAN.r-project.org and the Web server on muStat.rockefeller.edu. Knut M. Wittkowski is a Senior Research Associate at The Rockefeller University and Head of Biostatistics, Epidemiology, and Research Design at its Center for Clinical and Translational Science, New York, NY, USA. His research focuses on methods, meta data, and user interfaces to integrate nonparametric statistics into research and decision support systems. 相似文献
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王云平 《辽宁省交通高等专科学校学报》2007,9(4):30-32
本文介绍了用PID模糊控制技术中来解决在温度控制器控温过程中会产生的惯性温度误差问题。系统中的PID算法采用增量算法为基本算法,并按照实际应用做了适当的修改。经过实际测试,系统运行良好,证明在此医用理疗仪温度控制器中应用此PID算法取得了令人满意的结果。 相似文献
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周勇军 《铁道标准设计通讯》2019,(1):45-51
为了降低滑坡等不良地质在铁路建设和安全运营过程中产生的危害,在选线过程中需对区域内不良地质发生的风险进行评估。以蒙西至华中煤运通道工程黄土高原区为研究对象,基于遥感与GIS技术开展区内黄土滑坡风险评价研究,通过GIS技术分析滑坡与环境要素的内在联系,确定18个滑坡影响因子并进行定量研究;根据区内滑坡遥感解译成果和影响因子数据建立加权叠加模型,实现滑坡风险等级区域划分,并提出一种新的因子权重计算方法:通过建立滑坡因子变异系数在滑坡处与研究区的数学关系确定因子权重,具有客观可靠性;基于黄土滑坡风险评价结果,对拟选线位进行方案比选,提出最优线位通过方案。研究成果可应用于铁路工程选线设计和防灾减灾等工作。 相似文献
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宋艳琼 《广州航海高等专科学校学报》2015,(1):8-10,14
节能环保是国内外船舶的绿色发展道路.特别体现在海洋工程船的大型施工设备和施工设备的变频电力驱动技术上.简述了海洋工程船舶电网的谐波抑制思路,介绍一种谐波抑制的具体方案——3次谐波注入的高功率因数变流器,探讨了高功率因数无源变流器的设计电路,包括桥前采用3次谐波注入的高功率因数三相无源变流器的电路拓扑结构,并利用MATLAB 7.0/SIMULINK 6.0搭建了其仿真模型.仿真结果表明,使用3次谐波注入的高功率因数变流器既能对输入电流具有一定的谐波抑制效果又能提高功率因数. 相似文献
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上海港口经济驱动因素和演化过程分析 总被引:1,自引:0,他引:1
港口经济系统演化过程遵循着一般产业的生命周期模式。基于港口经济发展的演化模式和动力机制,提出上海港口经济评价指标体系,运用因子分析法并在SPSS的帮助下提取因子,分析1991~2005年上海港口经济的主导驱动因素,得出上海港口经济主要是由腹地经济、国际贸易、港口运作规模以及港口投资和经营能力等因素决定,在此基础上进而计算综合因子得分,考察上海港口经济演化过程。分析结果与1991~2005年间上海港口经济实际运行状况吻合,这说明该经济评价指标和分析方法具有实用性。 相似文献
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港口国监督检查选船如何避免产生“马太效应” 总被引:2,自引:1,他引:1
文中从概念、历史数据、数学模型角度分析了当前港口国监督检查中的目标因素评价体系,以及其存在阶段性正反馈所导致马太效应的原因,认为这种评价体系由于缺乏科学的动态正反馈限制以及连续性计算,而将不可避免地导致具有不良记录的船舶在一段时间内无法公正地获得与其他船舶一样的对待。笔者借此文介绍了各备忘录组织所采用的“黑名单-灰名单-白名单”船旗国分类方法,并从数学角度对其进行了分析,认为其能够较好地解决正反馈限制修正以及连续性计算问题,建议仿效其建立“黑名单-灰名单-白名单”船舶分类方法,通过登轮系数修正目标因素值作为选船的依据之一,从而给具有不良记录的船舶以彻底改善船况、重新获得信用的机会。 相似文献
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对晕车的传统研究认为晕车是视觉与平衡感官失衡造成矛盾引发的自我过度保护的后果。这个结论以及基于此结论开展的防治晕车措施已经持续了40余年。防治晕车的文献及市场上主流产品均以各种类型的晕车药物为主。本研究对现有晕车相关文献、专利、杂文等进行调查研究,总结分析出影响晕车主要因素为车内空气、车辆运动状态、视觉失衡、噪声、成员。使用对车辆乘员问卷调研的方法获取信息,对数据进行分析来研究晕车影响因素。数据表明晕车是一种发生频率高、普遍存在的乘车舒适性问题,具有明显的性别差异概率,是汽车行业发必须要面对和解决的重要问题之一。调查研究结果表明车内空气、车辆运动状态、视觉失衡三类诱发晕车的因素与文献研究结果一致。改善和防治晕车需要从车内空气、车辆运动状态、视觉失衡、噪声、成员这五类因素入手。使用车内空气的措施可以有效防治晕车现象的发生。清爽舒适的气味、降低温度、提高空气质量是三项有效的具体措施。 相似文献
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根据国内目前高速公路收费系统实际存在的状况。在分析收费系统总体要求和种种形式的基础上,给出了收费系统的合理选型配置方案。通过对各种收费系统通道通过量的讨论,提出了评价系数,并对提高评价系数的各种措施做了分析。 相似文献
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