从交易成本视角审视公平与效率悖论

不少论者出于理论和实践的动机,试图寻求公平与效率的完全统一。他们以“机会公平”为口实,来尝试取消和终结公平与效率悖论,交易成本的存在表明了这一努力的破产。在交易成本大于零的条件下,人们为了追求更高的经济效率,必然要在一定程度上牺牲公平,而保证了机会公平的强约束条件,就必然要降低和牺牲经济效率。可见,人们只能尽其可能地努力缓解公平与效率之间的张力,无法完全取消和终结公平与效率悖论。     

投资组合模型线性规划方法的研究

对文献[1]和文献[2]所给的线性规划方法,作了比较研究,得到结论:文献[2]的方法更易于操作,所得到的结果更符合实际.并且给出了一种确定文献[2]中的参数的方法.     

Denumerable state semi-Markov decision processes with unbounded costs,average cost criterion

This paper establishes a rather complete optimality theory for the average cost semi-Markov decision model with a denumerable state space, compact metric action sets and unbounded one-step costs for the case where the underlying Markov chains have a single ergotic set. Under a condition which, roughly speaking, requires the existence of a finite set such that the supremum over all stationary policies of the expected time and the total expected absolute cost incurred until the first return to this set are finite for any starting state, we shall verify the existence of a finite solution to the average costs optimality equation and the existence of an average cost optimal stationary policy.     

动态空域扇区划分管制员指派优化方法

以训练成本最小化为目标,构建了动态扇区划分管制员指派数学模型,通过引入虚拟扇区将模型设计成标准指派问题,为采用LINGO或MATLAB等工具求解奠定了基础.用空间集合抽象了管制员所管控扇区在扇区变动前后的位置关系,根据位置关系用代数式量化了指派成本.根据计算分析结果,提出了减少训练成本,缩短动态扇、区前置准备时间的建议措施.     

An analysis of transaction costs in participating life insurance under mean–variance preferences

Transaction costs with respect to distribution and administration play a crucial role for the performance of participating life insurance products. The aim of this paper is to investigate the impact of such initial and annual transaction costs on policyholder mean–variance preferences depending on the contract features, comparing a point-to-point guarantee, a cliquet-style guarantee, and a money-back guarantee with annual surplus component. We extend previous work by deriving analytical solutions for the maximum allowed initial transaction costs as well as the risk aversion parameter that ensure a given customer preference level for different contract types. We further conduct simulation analyses to identify key factors in regard to transaction costs. One main finding is that in the present setting, insurers can indeed charge higher costs for more complex products with cliquet-style features, and that the difference in costs between the various product types increases considerably in a low interest-rate environment. However, these results are heavily impacted and even reversed depending on the risk–return asset characteristics, as insurers with a riskier asset management strategy may no longer be able to charge higher transaction costs for complex products with a strong annual cliquet-style surplus participation component without reducing their attractiveness to customers.     

新准则借款费用资本化会计处理的思考

财政部颁布的《企业会计准则》对借款费用部分进行了修整,制定了《企业会计准则第17号——借款费用》,这对企业的会计核算产生了较大影响。文章立足新《借款费用准则》中的相关规定,简单分析了新旧准则的变化,对新《借款费用准则》在执行过程中所存在的问题进行的分析,进而就如何完善《借款费用准则》提出了相应的建议。     

福清湾围填海规划方案的费用效益分析

基于环境经济学的理论和方法,建立了效益和费用的评估模型,对福清湾3个围填海规划方案进行费用效益分析,获得如下结果：在8%贴现率下,方案1、2、3的费用效益比值分别为1.30、0.478、0.502,在4.5%贴现率下,分别为1.170、0.414、0.436,从环境经济学的角度看方案2和方案3是不可行的.结果还显示,围填海所带来的外部费用即生态环境损失相当显著,是填海工程成本的3至15倍.显然,审慎科学地进行围填海的规划与决策十分重要.     

A cutting plane approach to capacitated lot-sizing with start-up costs

We consider a mixed integer model for multi-item single machine production planning, incorporating both start-up costs and machine capacity. The single-item version of this model is studied from the polyhedral point of view and several families of valid inequalities are derived. For some of these inequalities, we give necessary and sufficient facet inducing conditions, and efficient separation algorithms. We use these inequalities in a cutting plane/branch and bound procedure. A set of real life based problems with 5 items and up to 36 periods is solved to optimality.     

Dynamic scheduling to minimize lost sales subject to set-up costs

We consider scheduling a shared server in a two-class, make-to-stock, closed queueing network. We include server switching costs and lost sales costs (equivalently, server starvation penalties) for lost jobs. If the switching costs are zero, the optimal policy has a monotonic threshold type of switching curve provided that the service times are identical. For completely symmetric systems without set-ups, it is optimal to serve the longer queue. Using simple analytical models as approximations, we derive a heuristic scheduling policy. Numerical results demonstrate the effectiveness of our heuristic, which is typically within 10% of optimal. We also develop and test a heuristic policy for a model in which the shared resource is part of a series network under a CONWIP release policy. This revised version was published online in June 2006 with corrections to the Cover Date.