Drivers of expected returns in Istanbul stock exchange: Fama–French factors and coskewness

We investigate the impact of coskewness on the variation of portfolio excess returns in Istanbul Stock Exchange (ISE) over the period July 1999 to December 2005. We form portfolios according to size, industry, size and book-to-market ratio, momentum and coskewness and compare alternative asset pricing models. The traditional capital asset pricing model (CAPM) and the three-factor model of Fama and French are tested in the multivariate testing procedure of Gibbons–Ross–Shanken (1989). Coskewness is introduced as a fourth factor and its incremental effect over CAPM and Fama–French factors is examined both in multivariate tests and in cross-sectional regressions. The findings reveal that coskewness is able to explain the size premium in ISE. Hence, the basic two-moment CAPM without the coskewness factor would underestimate the expected return of size portfolios. Multivariate test results indicate that coskewness reduces the pricing bias, albeit insignificantly. Cross-sectional analysis uncovers that coskewness has a significant additional explanatory power over CAPM, especially for size and industry portfolios. However, coskewness does not have a significant incremental explanatory power over Fama–French factors in ISE.     

The Application of Sensitivity Analysis on Comprehensive Transportation Evaluation

Comprehensive transportation evaluation objects using multi-objective decision method is a process of choosing the best one from a few objects through calculating, analyzing, and comparing the index system. The result may be different because of the difference of the index weight and index value. Therefore, sensitivity analysis should be one of the necessary parts of the decision-making. It is desired to give the index with higher sensitivity and its varying scope to control the index strictly during the execution process. This paper derives transfer index weight, which changes the rank evaluation order of the projects. Meanwhile, a simple, effective and practical method based on sensitivity district and sensitivity matrix is proposed for the sensitivity analysis of decision-making. As an example, the index sensitivity in decision-making of some provinces comprehensive transportation objects, and their influence on the final decision are discussed.     

城市群建设中交通网络体系整合与优化的研究——以湖南“3＋5”城市群为例

交通网络体系的发展和完善是城市群建设的先决条件和重要手段。在归纳总结交通网络体系对城市群建设的影响机理作用及其促进城市群发展的路径基础上,结合湖南“3＋5”城市群的发展实际,指出在城市群建设中应以科学发展观为指导,适度超前发展并完善交通网络体系,提高其综合服务能力等措施以满足城市群建设对交通基础网络的需求。     

试论乾隆以后清朝对西北边疆少数民族的贸易政策

清朝时期西北边疆地区农业经济与牧业经济之间天然的互相依赖性使各民族和地区之间的商业贸易显得十分重要。清政府在商业贸易方面,主要是尽可能地动用国家机器职能,实行商业贸易垄断,控制与哈萨克、布鲁特之间的绢马贸易和茶马贸易,以之作为控制、羁縻少数民族的手段。对民间商人所从事的各民族之间的直接民间经济交往的贸易,尽量予以限制,以达到最终稳定社会的目的,这种贸易限制政策直接影响到了西北边疆地区的经济发展。     

交通运输投资宏观经济效应分析——基于乘数模型的应用

文章基于乘数理论及投资乘数模型对交通运输投资宏观经济效应进行分析,设置了边际交通消费倾向,并推导出交通最终消费需求模型;运用交通消费倾向,证明了交通运输发展对推动产业结构优化的作用和缩小地区差距的功能。     

一种非市场因素导致的铁矿石价格上涨——基于博弈的分析

通过一个可重复博弈模型,揭示了中国在国际铁矿石贸易中面临由非市场因素造成的价格上涨问题,认为,造成这种现象的根本原因是中国在铁矿石贸易中的市场地位并没有随着进口量的提高而提高,并从资源安全角度提出了应对策略。     

基于交通视角的新疆城市等级体系演变研究

通过主成分分析、集中度系数、非均衡系数以及改进的重力模型对新疆各城市的交通运输综合水平、复合流量的集中程度和基于复合流量的城市引力及引力节点分析,得出结论:①1985—2005年新疆城市交通运输综合水平变化明显,国道和北疆铁路沿线城市发展水平较高,发展水平较低的城市主要集中在南疆,且比较分散;②集中度系数波动明显,乌鲁木齐、克拉玛依、昌吉、阿克苏等城市对新疆客货流影响较大,而区域非均衡系数较低,呈现明显缩减的趋势;③受绿洲城镇发育程度和自然地理条件影响,各等级节点数量变化不大。乌鲁木齐、克拉玛依、昌吉、石河子在不同年份对新疆各城市的影响较为明显,节点等级较高。④基于交通视角的城市体系呈现出交通运输中心区域不断强化,二级节点城市变化明显,经过20年的演变,基本形成了以乌鲁木齐都市圈为核心,以石河子为次级中心,以喀什和米泉为三级中心,以克拉玛依、伊宁、乌苏、库尔勒为重要节点的城市体系。     

低碳发展视角下交通业能耗效率及与经济增长关系的动态分析——以广东为例

本文从节能减碳的角度分析了广东交通业能源消耗和交通业增加值与全省经济增长、能源消耗总量的相互关系,并与全国数据进行了对比分析,结果发现：（1）交通业增加值对广东经济增长的直接贡献不明显;（2）交通业能源消耗量变动是全省能源消耗总量变动的单向格兰杰原因,说明交通业能耗量在全省能源消耗总量中占据重要地位,预示广东交通业节能降耗的空间很大、任务很重;（3）能源消耗量增加并不必然导致广东经济增长;（4）广东交通业的单位增加值能耗高于全省单位GDP能耗平均水平,而且远超过全国交通业的平均能耗水平,高能耗特征依旧严重;（5）广东的交通业增加值、交通业能耗、全省GDP和全省能耗总量的互动关系与全国的表现略微不同,原因可能是由于地区交通业增加值统计方法的缺陷造成。     

The hidden value of air transportation infrastructure

Air transportation is a key strategic asset in that it provides access to markets and thereby enables the economic development of nations. Thus, in order to maintain their competitiveness in a global economy, countries must invest in air transportation infrastructure to ensure their ability to meet current and future demand for aviation services. The objective of this paper is to develop and illustrate a methodology for evaluating the strategic value of air transportation infrastructure, in particular the benefits associated with the ability to react quickly to changes in the market. The hypothesis is that by recognizing and taking advantage of this strategic value, it may be possible to design better policies for aviation infrastructure delivery.The methodology developed here uses system dynamics to model different strategies for infrastructure delivery. These strategies are defined by three variables: the amount of capacity increase, the time to deliver the capacity and the congestion threshold that triggers the need for capacity delivery. Monte Carlo simulation is used to take into account multiple sources of uncertainty. The model shows that a strategy of capacity delivery based on small increments and short response times can yield more benefits than strategies that consider large capacity increases and long response times. Furthermore, in the specific airport example considered here, it was found that a congestion threshold of 75% should be the trigger for capacity enlargements if strategies based on small capacity increments and 1 or 5 years to increase capacity are considered. The lesson for decision-makers is that congestion delays must be addressed with foresight.     

论铁路货运向现代物流转变

随着我国高铁的快速建设,以及铁路货运机制的不断改革,铁路货运发展现代物流存在非常好的机遇。铁路运输为了提高市场份额,适应市场需求,应采取众多改革方针。通过运用SWOT方法,对我国铁路货运发展现代物流进行了分析,指出了其存在的优势、劣势、机遇与威胁,并提出铁路货运在发挥自身优势、优化货运组织的同时,要充分利用路网资源,进一步加强铁路货运改革,优化两端运输组织,完善“门到门”物流运输,积极拓展铁路货运增值业务,大力发展协同运输,为铁路货运发展现代物流提供有力保证。