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361.
Many western countries have seen a plateau and subsequent decrease of car travel during the 21st century. What has generated particular interest and debate is the statement that the development cannot be explained by changes in traditional explanatory factors such as GDP and fuel prices. Instead, it has been argued, the observed trends are indications of substantial changes in lifestyles, preferences and attitudes to car travel; what we are experiencing is not just a temporary plateau, but a true “peak car”. However, this study shows that the traditional variables GDP and fuel price are in fact sufficient to explain the observed trends in car traffic in all the countries included in our study: the United States, France, the United Kingdom, Sweden and (to a large extent) Australia and Germany. We argue that the importance of the fuel price increases in the early 2000s has been underappreciated in the studies that shaped the later debate. Results also indicate that GDP elasticities tend to decrease with rising GDP, and that fuel price elasticities tend to increase at high price levels and during periods of rapid price increases.  相似文献   
362.
363.
In Germany, many universities have student tickets that are bargained for between student representatives and public transport companies, approved by referendum, and mandatory for all students. They allow the use of public transport at no additional cost. I analyze such a scenario in a theoretical model as an example of a flat-rate ticket for public transport which is implemented by majority decision. The mandatory character of the ticket reduces transaction costs like marketing and ticket inspection, reducing the ticket price and thus the students’ commuting expenses. However, there is a countervailing effect. Students face and rationally expect zero marginal monetary commuting costs, so that new students choose a place of residence which is relatively far from the university. This in turn raises the equilibrium ticket price. It may even be the case that students would be better off if such a ticket had never existed. Nonetheless, they always vote for it in referenda, because accepting the high price is optimal given their place of residence. After laying out the model, I analyze an optimal policy, which consists, for example, of subsidizing student dorms at an efficient distance to the city center.  相似文献   
364.
定量分析城市轨道交通对沿线土地价值的影响,是通过土地价值捕获将外部效益内部化, 解决中国新型城镇化过程中城市轨道交通财务可持续的关键问题。本文在开源数据环境下,获 取2011—2016年北京市二手房交易数据,采用特征价格模型(HPM)分析北京城市轨道交通新建 线路对沿线住宅价格增值的时空效应。研究表明:与全局常参数的多元线性回归模型(MLR)、空 间滞后模型(SLM)、空间误差模型(SEM)和空间杜宾模型(SDM)相比,局部变参数的地理加权回归 模型(GWR)拟合效果更优,可以更好地消除残差的空间效应,刻画轨道交通与土地价值关系的空 间异质性。城市轨道交通带来的可达性提升对沿线80%以上住宅小区的房价具有显著的正效 应,住宅价格增值比率随地铁站距离递远递减,且具有显著的空间异质性。轨道交通对住宅价格 的影响在空间上具有网络化效应,新建线路不仅会改变周边房价,对城轨网络其他位置的住宅也 具有影响。城市轨道交通对住宅价格的影响范围为1 km,在该范围内,住宅价格受到的增值效应 在 2011—2016 年基本稳定,约为 3%;受新线直接影响区域的住宅价格会产生相对更大的提升 (0.02%~0.22%)。  相似文献   
365.
This paper deals with the question of whether the capability of car drivers to estimate the cost of a new hypothetical, highly differentiated congestion charge influences their decision to change travel behaviour. The analysis makes use of an integrated choice and latent variable model (ICLV) which merges classic choice models with the structural equation approach (SEM) for latent variables. This hybrid model improves the explanatory power considerably compared with a conventional discrete choice model. The results suggest that charge complexity decreases the resistance in considering behavioural changes. Car drivers tend to avoid a travel option where the price is not known beforehand, a phenomenon known as ambiguity avoidance.  相似文献   
366.
运用停时理论及粒子选举交互作用系统,建立了一个包含两类投资者的股票价格模型,用以描述证券市场的单只证券价格过程波动的统计特性.基于统计分析方法,证明了标准化随机价格过程收敛于相应Black-Scholes模型的分布.讨论了该价格过程模型下的欧式未定权益的定价和套期保值问题.  相似文献   
367.
根据以往铁路建设项目利用外资土建工程采用价格指数法调整价差的实际情况,通过和铁道部实行的价差系数法进行价差调整进行对比分析。归纳出价格指数法调整价差存在的7个方面的差异和问题。分别为调整范围的差异,非调整因子的差异,调整年度的差异,劳务费调整的差异,钢材、木材、水泥及其他材料权重的差异,机械使用费调整的差异,调差地区划分的差异。并针对上述差异和问题进行分析,找出存在差异的主要影响因素,总结出一套既符合铁路项目投资管理及真实反映工程造价水平,又符合铁路实际情况及与国际惯例接轨的外资土建工程价格调整公式。  相似文献   
368.
为深入分析航空公司动态价格竞争的复杂性,运用非线性动力学的分支理论,构建了基于差异化的航空公司动态价格竞争模型,依据动力学稳定性判定条件,讨论了该模型均衡点的存在性、存在个数与稳定性,数值仿真了不同条件下模型复杂的动力学行为.仿真结果表明,航空公司价格调整速度对模型的稳定性有明显的影响,一旦价格调整速度超过某一临界值,系统将表现出分岔、混沌等复杂的动力学现象;与Nash均衡利润相比,在混沌状态下航空公司的利润均显著下降;差异化战略对航空公司定价、利润有重要影响,保持和加强对竞争对手的差异化优势有助于自身获得更大的市场竞争优势.  相似文献   
369.
唐俊 《城市道桥与防洪》2013,(6):200-203,10,9
"政府投资建设项目",是随着我国的经济和政治体制的改革而逐步发展形成,在实践中,又被称为"公共财政投资项目"或者"国家建设项目"。主要包括:财政预算内外资金(含国债资金)投资项目;国家主权外债资金项目;使用各类专项建设资金项目;法律、法规和各级人民政府规定的其他政府投资项目。该文阐述了"政府投资建设项目"全过程道路控制的若干要点。指出:"政府投资建设项目"的全过程造价控制,贯穿于立项、方案设计、招投标、实施、竣工验收、审价审计、绩效评价等每一个阶段。为保证项目的投资目标的实现,取得良好的经济和社会效益,应根据每个阶段工作的特点,利用科学的管理方法和有效的控制措施,以达到控制工程造价的目的。  相似文献   
370.
Land development impacts of mass transit have long been studied in the developed economies. Yet relatively little is known by the outside world about the Chinese experience due to China's rather short history in the development of modern mass transit and land/property market. This paper attempts to fill the gap by presenting evidence from China, with a detailed case study of Beijing. Selecting three newly built suburban transit lines in Beijing, the study examined land development context and estimated hedonic housing price models to measure the proximity premiums associated with these three lines. The empirical evidence in Beijing, one of the first tier mass transit cities in China, shows that investments in mass transit can have significant and positive impacts on land development. Properties with transit proximity enjoy sizable price or value premiums. The study also confirms the international experience: transit impacts on land development are unlikely to occur automatically; they rely greatly on supportive regional and site conditions. Integrated planning and design for mass transit and land development are critical to expand and maximize the return of transit investments.  相似文献   
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