Collective Risk Control and Group Security: The Unexpected Consequences of Differential Risk Aversion

We provide an analysis of odds‐improving self‐protection for when it yields collective benefits to groups, such as alliances of nations, for whom risks of loss are public bads and prevention of loss is a public good. Our analysis of common risk reduction shows how diminishing returns in risk improvement can be folded into income effects. These income effects then imply that whether protection is inferior or normal depends on the risk aversion characteristics of underlying utility functions, and on the interaction between these, the level of risk, and marginal effectiveness of risk abatement. We demonstrate how public good inferiority is highly likely when the good is “group risk reduction.” In fact, we discover a natural or endogenous limit on the size of a group and of the amount of risk controlling outlay it will provide under Nash behavior. We call this limit an “Inferior Goods Barrier” to voluntary risk reduction. For the paradigm case of declining risk aversion, increases in group size(wealth) will cause provision of more safety to change from a normal to an inferior good thereby creating such a barrier.     

人口结构与金融市场风险结构:风险厌恶的生命周期时变特征

金融市场中要更多考虑参与主体"人"的因素。经典理论模型通常设定风险厌恶系数为不随年龄而变的常数。本文构建模型并运用微观和宏观数据,刻画和验证经济主体风险厌恶在生命周期中的时变特征。微观视角下风险厌恶受年龄正向影响,宏观视角下金融市场和行为风险厌恶均随平均年龄上升而上升。少年人口占比负向影响风险厌恶;中、老年人口降低风险偏好,风险态度趋于保守。风险厌恶在生命周期内存在时变性,表现为年龄越大风险厌恶越强,可谓"江湖越老,胆子越小"。这对于后续建模中设定风险厌恶可变系数有借鉴意义。年龄改变风险态度和风险资产组合,使得人口年龄结构系统性影响金融市场风险结构。因此,本文对于从人口学视角预判未来金融市场风险结构也具有一定参考价值。     

Heterogeneity of First-order Risk Aversion and the Equity Premium

I show that stockholders and non-stockholders can coexist in equilibrium even if securities markets are perfect and complete. This is due to a heterogeneous safety inclination, which is defined as heterogeneity in first-order risk aversion (Segal and Spivak, 1990). A static two-security market model is analysed by the mean–standard deviation approach, where safety inclination is described by the degree of the marginal rate of substitution between the mean and the standard deviation at a certain point. In equilibrium, aggregate shocks may be concentrated on stockholders, which may lead to a high equity premium.
JEL Classification Numbers: D81, E44.     

Risk Aversion and the Full Costs of Rent-Seeking*

Risk aversion is frequently postulated as one of the factors that lead to under-dissipation of rents. However, the formal analyses which have supported this contention and suggested that the effects can be large have focused solely on the expenditures of contestants, ignoring the associated costs of risk. The paper argues that this omission is wrong in principle, and that when corrected the presence of risk aversion in fact leads to substantial increases in the extent of rent dissipation, although an exception is when there is a very strong combination of risk aversion and asymmetry.     

农户土地退出风险认知及规避能力的影响因素分析

以重庆市l 829户农户的调查数据为基础,对农户土地退出风险认知及规避能力进行分析,并运用有序Probit模型,分析了影响农户宅基地、承包地退出风险规避能力的因素及方向.结果表明:①多数农户认为土地退出风险较高,同时农户对于退出承包地较宅基地存在更大的顾虑,农户更倾向退出宅基地;另一方面,多数农户规避土地退出风险能力较弱,相比承包地,农户具有更强的宅基地退出风险规避能力.②宅基地风险规避能力来看,户主年龄、家庭有无稳定城镇住所、本村是否在进行农民新村建设、退地后能否享受高水平城镇社保对农户宅基地退出风险规避存在显著正向影响;家庭有无养殖经营对退出风险规避存在显著负向影响.③承包地风险规避能力来看,户主年龄、户主是否购买商业保险、家庭有无稳定非农收入、退地后能否及时获得就业培训与援助、退地后能否享受高水平城镇社保对农户承包地退出风险规避存在显著正向影响;家庭有无养殖经营对农户承包地退出风险规避存在显著负向影响.④影响农户宅基地退出风险规避能力的因素少于影响农户承包地退出风险规避能力的因素,同一因素也可能对农户宅基地、承包地退出风险规避能力产生不同的影响.     

油气勘探开发技术研发风险评价与规避

运用期权观点分析油气勘探开发技术研发风险,依据风险来源分类即技术风险、生产风险、市场风险、管理风险、财务风险与环境风险构建油气勘探开发技术研发风险评价指标体系,确定各二级风险指标的评价值,并进行规范化处理,利用前馈神经网络预测勘探开发技术研发的风险。最后结合石油企业技术研发特点提出风险回避、风险转移、风险弱化、风险控制和风险监控系统化风险规避机制。     

气候变暖的第一影响因素及我国的应对

全球气候变暖已是人们逐渐接受的事实,由于大气中二氧化碳等气体含量的升高引起的温室效应是导致全球气温变暖的显著原因。经过统计分析发现,大气中碳含量的增加与全球森林面积减少、化石能源燃烧增加的碳排放高度相关,但年均0.4%增速的大气中的碳含量是与按年均0.2%速度递减的全球森林面积存在显著的统计上的因果关系,乱砍滥伐、开发耕地等导致的全球森林面积的减少是大气中二氧化碳含量增加的格兰杰因果关系原因,从而构成全球变暖的第一影响因素。二氧化碳排放量的增加一直比较平稳,年增速在2.2%左右,它与大气中的碳含量的增加虽然相关,但因果关系统计上并不显著,也不是其格兰杰因果关系原因,这一结论与IPCC的报告中二氧化碳排放量是全球变暖的主要原因的结论并不完全一致。据此,我们提出中国应对全球变暖时谨防陷入碳排放陷阱。     

Overlapping Generations or Infinitely-Lived Agents: Intergenerational Altruism and the Economics of Global Warming

Do we need an overlapping generations model for the economics of global warming? To answer this question, an infinitely-lived agent (ILA) approach and an overlapping generations (OLG) model are contrasted. ILA and OLG can be viewed as polar representations of intergenerational altruism. With ILA an immortal agent acts through his investment/savings decisions as trustee on the behalf of the future generations. With OLG, agents need not behave altruistic. They simply save during working years and dissave completely during retirement. Nevertheless, ILA and OLG must not differ in their implication for greenhouse policy. Greenhouse gas abatement is a straightforward alternative to physical capital formation and, even without altruism, each age cohort has an incentive to provide current abatement in order to reduce future damages attributable to climate change. Indeed, under reasonable assumptions and parameter values, our simulations reveal such an invariance result. Provided carbon taxes are the only policy tool and tax revenues are recycled through socially mandated rules, projections of economic growth, climate change and energy consumption are only insignificantly affected by the choice of approach.     

Risk Aversion and the Investment Horizon: A New Perspective on the Time Diversification Debate

Investment managers generally subscribe to the principle of time diversification. This implies that a larger portion of the portfolio should be devoted to risky assets as the investment horizon increases. In contrast, academics have shown that for investors with utility functions characterized by constant relative risk aversion, the optimal asset-allocation strategy is independent of the investment horizon. The relative risk aversion in these studies is assumed to be constant both with respect to wealth as well as investment horizon. We suggest a utility function that explicitly captures the notion that individuals are more risk tolerant when the investment horizon is long, thereby validating the intuitively appealing time diversification argument.     

全球变暖与三江平原湿地的变化

全球变暖已经成为不争的事实。沼泽湿地是各种主要温室气体的源和汇,在全球气候变化中有着特殊的地位和作用。三江平原湿地是我国最大的沼泽分布区,有着重要的生态意义。本文总结了全球气候变化大背景下,在三江平原湿地开展的科学研究的内容及成果。     

全球气候变暖语境下中国低碳农业发展研究文献综述

自工业革命以来,人类生产和生活方式过度地依赖能源与科技,长期开放式与高耗能运作累积的一个显著结果就是大量排放的温室气体所导致的温室效应使全球气候变暖。在气候变暖的维度上,农业是把双刃剑,它既有碳排放功能又有碳汇功能,因此发展低碳农业是减源增汇的必然途径。文章梳理了中国发展低碳农业研究的主要成果,包括低碳农业与农产品安全、低碳农业技术体系的构建、低碳农业的生态产业链与发展现状等,并预期了可能的研究方向。     

The Global Disconnect: The Role of Transactional Distance and Scale Economies in Gravity Equations

Recent empirical analyses show that asset flows can be modelled by the same 'gravity' equations that trade economists have used so successfully for the past few decades. This is something of a surprise. Trade economists do not yet have a unified theory of why gravity models should work‐and the situation is worse for asset flows. Reasonable theories would predict that greater distance between countries should generate more asset flows rather than less as the econometric results seem to consistently show. In this paper we discuss how host and source country GDPs, language, and distance the core explanatory variables in the traditional gravity models‐fare in trade and asset flows estimations. While the 'distance puzzle' is not resolved, it is considerably reduced by going beyond consideration of physical distance to concepts of transactional distance and scale economies.     

地球暖化与温室气体的排放——中日贸易中的CO2排放问题

本文结合中日两国国民收入及外贸基本经济数据,利用数学方程把经济因素、环境因素、国际关系联系起来,建立了环境与经济综合分析的模型,测算经济与环境之间的数量关系,同时为中日两国的环境政策合作、能源管理和可持续发展研究提供了基础数据。     

全球供应链管理的效率、均衡和风险问题

伴随着全球化与竞争一体化的加速,外包、合作、多赢和核心竞争力的构建等经营战略和模式的创新,供应链显现出前所未有的竞争优势。但同时,也面临着一些全新的挑战：如供应链复杂性和脆弱性,供应链的灵活性和依赖性,供应链的精益化与弹性,局部优化和总体均衡等。本文从均衡策略和风险管理的角度,针对全球化背景下由于不确定性剧增而导致的诸多供应链管理的悖论问题进行了剖析,以期加强对供应链及供应链风险管理意识,提供建立起一般性的分析框架,推进供应链风险分析和风险管理以及不确定性的问题的系统性研究。     

绿色流通:区域经济可持续发展的切入点——以湖北孝感市为例

在市场日益成为资源配置主要方式的今天,绿色流通势必将成为21世纪经济发展的新趋势.在这种现实背景下,孝感在商品流通领域存在的问题日益严重.针对这一问题,文章采用理论和实践相结合的研究方法,主要对孝感传统流通的现状及存在的问题进行分析,并提出建立完善的绿色流通体系的运作思路和具体措施,以促进孝感经济的可持续发展.     

福建风险投资业“十五”发展重点

风险投资主要指向属于科技型的高成长性企业提供创业资本,并为其提供经营管理和咨询服务,以其在被投资企业发展成熟后,通过股权转让获取中长期资本增值收益的投资行为。上个世纪80年代以来,以美国为首的西方发达国家风险投资事业迅猛发展,极大地推进了国际高新技术产业的发展。近几年来,中国风险投资业也发展很快,北京、上海、深圳风险投资业三大中心正在形成。相比之下,福建省风险投资事业发展滞后,高新技术创业风险投资机构少,资本规模小、