On the timeliness of tax reform

This paper analyzes efficient government reactions to unanticipated tax avoidance. Quickly reforming tax laws to reduce the effectiveness of new tax avoidance techniques prevents widespread adoption, but indirectly encourages the rapid development of new avoidance methods if prior users are permitted to retain their tax benefits. Tax reforms that immediately prevent new avoidance mean that innovators need not fear imitation by competitors, and cannot rely on copying the innovations of others. Such an activist reform agenda diverts greater resources into tax avoidance activity, and might thereby lead to a faster rate of tax base erosion, than would a less reactive government strategy. Efficient government policy therefore entails either the retroactive elimination of tax savings, with possible associated costs, or else a deliberate pace of tax reform in response to taxpayer innovation.     

Keynes, uncertainty and interest rates

Uncertainty plays an important role in The General Theory, particularlyin the theory of interest rates. Keynes did not provide a theoryof uncertainty, but he did make some enlightening remarks aboutthe direction he thought such a theory should take. I arguethat some modern innovations in the theory of probability allowus to build a theory which captures these Keynesian insights.If this is the right theory, however, uncertainty cannot carryits weight in Keynes's arguments. This does not mean that theconclusions of these arguments are necessarily mistaken; intheir best formulation they may succeed with merely an appealto risk.     

Linking scenarios across geographical scales in international environmental assessments

The development and analysis of scenarios or plausible futures has evolved to be a useful approach for dealing with uncertainty about future developments in a structured and integrated manner. Commonly, scenario exercises have focussed on processes at one specific geographic scale. Recently scenario-based approaches have also been used to address multi-scale processes or to link scenarios developed at various geographical scales with each other in order to better understand the interaction of processes across scales.The level of interconnectedness across scales will vary, and depends largely on the approaches used to develop multi-scale scenarios. We distinguish five levels of interconnectedness scenarios may display across scales: (a) Equivalent, (b) Consistent, (c) Coherent, (d) Comparable, and (e) Complementary. Furthermore, we describe five different types of coupled scenario development processes: (a) Joint, (b) Parallel, (c) Iterative, (d) Consecutive, and (e) Independent.Based on this nomenclature, the relationship between the level of interconnectedness of scenarios and the degree of coupling of scenario development processes across geographical scales is discussed. Which process is best suited and how much interconnectedness is needed, will depend both on the focal issue and the primary purpose of the scenario exercise, i.e. whether the aim is education, scientific exploration, or decision-support.     

不确定性与早期劳动合同 --契约理论的一个新发展

在劳动力市场上 ,劳动者和厂商未来的生产率都具有不确定性。早期劳动合同或签约由于一方面可以保证劳动者被排除在劳动力市场之外 ,同时也保证了厂商被排除在事后职位市场的风险之外 ,因而厂商和劳动者具有签订早期劳动合同的激励。尽管早期劳动合同或签约存在成本 ,但只要事前利益超过事后无效率的损失 ,那么早期劳动合同或签约就会发生。对于那些不能获得完全市场保险的人来说 ,签约是一种帕累托最优。早期劳动合同或签约是市场失灵的一种证明 ,早期劳动合同是一种不完全合同 ,也是一种非正式合同 ,它是对契约理论的一个发展。     

参与、不确定性与投资秩序的生成和演化——解读投资者动机和预期的另一个视角

不同于现有主流理论把投资者的动机和预期理解为投资者实现其效用最大化的计算过程 ,本文认为投资者的动机和预期表明投资者对于投资决策的一种参与 ,并在此基础上提出一个解释框架。这一解释框架把投资者动机和预期所包含的对于投资决策的参与态度及感受定义为参与指数 ,不同的参与指数形成不同的投资者群体 ,而不同投资者群体的互动 ,决定着对投资决策最终发生实际作用的投资秩序的生成与演化 ,不确定性正是刻划了投资秩序生成与演变的主观性和非设计性。     

浅析资本弱化与外资避税

随着现代资本结构理论的发展,国内外企业都在学习如何在实务中对其加以灵活应用,使企业价值最大化.资本弱化就是这样一种应用,其目的在于企业通过资本结构安排,改变其纳税义务,起到避税的作用.目前,来自发达国家的外资企业在这一避税手法的使用上已达到了十分成熟的阶段,再加上我国现行税制框架尚未对资本弱化进行识别、规范和控制,造成了我国大量的税收利益流失.另外,在我国已逐渐认识到问题的紧迫性的情况下,如何进行监管和控制也是一个很大的技术难题.     

Uncertainty and sustainability in the management of rangelands

We analyze a dynamic and stochastic ecological-economic model of grazing management in semi-arid rangelands. The ecosystem is driven by stochastic precipitation. A risk averse farmer chooses a grazing management strategy under uncertainty such as to maximize expected utility from farming income. Grazing management strategies are rules about which share of the rangeland is given rest depending on the actual rainfall in that year. In a first step we determine a myopic farmer's optimal grazing management strategy and show that a risk averse farmer chooses a strategy such as to obtain insurance from the ecosystem: the optimal strategy reduces income variability, but yields less mean income than possible. In a second step we analyze the long-run ecological and economic impact of different strategies. We conclude that a myopic farmer, if he is sufficiently risk averse, will choose a sustainable grazing management strategy, even if he does not take into account long-term ecological and economic benefits of conservative strategies.     

SZJ-1三轴智能校验台标准装置测量不确定度的评定方法

简要介绍了建立SZJ-1三轴智能校验台标准装置的必要性及原理框图。详细论述了其测量不确定度的评定方法。并对标准装置的测量不确定度进行了验证。     

The implications,challenges and benefits of a complexity-orientated Futures Studies

Complexity science is increasingly cited as an essential component of a Futures Studies (FS) capable of assisting with the wide-ranging and complex societal problems of the 21st century. Yet, the exact implications of complexity science for FS remain somewhat opaque. This paper explicitly sets out the challenges for FS that arise from six complexity science concepts: (1) irreversibility of time (2) path dependence 3) sensitivity to initial conditions (4) emergence and systemness (5) attractor states (6) complex causation. The discussion highlights the implications of these challenges for FS tools such as horizon scanning and weak signals, and sets out the benefits of overcoming the challenges to create an explicitly complexity-orientated FS. The discussion concludes with a set of questions summarising the challenge for FS from complexity science with the aim of stimulating a discussion as to how they can be met. The concluding remarks make some initial suggestions in this regard.     

Bailout uncertainty in a microfounded general equilibrium model of the financial system

This paper develops a micro-founded general equilibrium model of the financial system composed of ultimate borrowers, ultimate lenders and financial intermediaries. The model is used to investigate the impact of uncertainty about the likelihood of governmental bailouts on leverage, interest rates, the volume of defaults and the real economy. The distinction between risk and uncertainty is implemented by applying the multiple priors framework to beliefs about the probability of bailout.Results of the analysis include: (i) An unanticipated increase in bailout uncertainty raises interest rates, the volume of defaults in both the real and financial sectors and may lead to a total drying up of credit markets. (ii) Lower exante bailout uncertainty is conducive to higher leverage, which in turn raises moral hazard and makes the economy more vulnerable to expost increases in bailout uncertainty. (iii) Bailout uncertainty affects the likelihood of bubbles, the amplitude of booms and busts as well as the banking and the credit spreads. (iv) Higher bailout uncertainty is associated with higher returns’ variability in diversified portfolios and higher systemic risks, (v) Pre-crisis expansionary monetary policy reinforces those effects by inducing higher aggregate leverage levels. (vi) The larger the change in bailout uncertainty and the change in aversion to this uncertainty, the stronger the pre-crisis buildup and the deeper the ensuing crisis.A central policy implication of the analysis is that the vaguest is bailout policy prior to a crisis, the lower is the magnitude of investments destroyed or missed due to errors in evaluating bailout and other intervention policies. On the other hand, the clearer is bailout policy upon the eruption of a crisis, the smaller the contraction of credit and the destruction of investment activity.