风险投资合约中最优努力与收益分享比的关系

构建了多阶段风险投资的委托代理模型,同时考虑了投资家和企业家两方面的努力,对企业家和投资家的最优努力水平与收益分享系数的关系进行了理论分析和数值模拟,随后考虑了企业家公平偏好对努力水平的影响.发现随着互补程度的增大,两者努力水平对分享系数的反应曲线趋于重合.公平偏好的加入使得投资家和企业家对自身收益更加敏感.     

风险资本的组合投资最优化模型研究

利用委托代理理论建立了风险资本的组合投资最优化模型,通过该模型给出了项目数和收益分配比例的最优解,并分析了组合投资的项目数和收益分配比例对风险投资家和企业家努力水平的影响。     

两阶段双任务委托代理情形下煤矿安全管理激励机制

煤矿企业安全监管效能低下一直困扰煤炭行业的重大问题,监管效能低下的根本原因是煤矿企业的委托代理激励机制的失衡,进而导致在安全产出中搭便车行为大量存在.煤矿的委托代理问题是一个多阶段多任务的动态问题,因此构造了一个两阶段双任务的委托代理模型.在模型第二阶段中煤矿职工能够通过对第一阶段信息的学习了解自身努力与回报之间的映射,进而决定自己在两项任务的委托代理中努力程度的付出.通过模型的分析得到:煤炭生产任务的正向激励会对煤矿职工在安全产出方面的努力程度造成负面的影响,且煤矿职工在完成安全产出任务方面的能力越高,在此方面努力程度就下降的越慢,降低截断水平能够导致更多的职工在第二阶段的工作中提高努力水平,进而减少搭便车行为.     

基于股权——债权条件下风险投资的激励机制分析

运用博弈论中委托—代理理论对股权—债权条件下风险投资的激励机制进行了系统分析.根据风险投资家提供股权—债权与风险企业家提供股权融资的假设条件构造了一个基本博弈模型,并对模型进行了推广.研究发现:风险企业家的投资不仅有融资功能,而且还可以作为一种信号传递改变风险投资家的投资信念,使之对项目前景更乐观;扩展模型比基本模型更能改善风险企业家的投资行为,使之投入更多资金和给予风险投资家更高激励;此外,扩展模型更能消除股权—债权投资比例的相互替代性.     

风险内生的委托代理模型研究

证券投资基金的委托代理关系与一般的委托代理关系不同,在一般的委托代理关系中,产出的风险是外生的,而基金产出的风险是内生的,即风险是由基金管理人来选择的.在模型假设的背景下,在不考虑基金管理人的努力成本时,基金委托代理关系中不存在道德风险问题.如果考虑基金管理人的努力成本,当其行为不可观测时,基金投资者无法通过契约参数的变化来影响基金管理人的努力水平,但此时投资组合的风险水平将低于基金管理人行为可观测时的情况.实证研究证实了基金收益分享比例与基金管理人努力程度无关的模型推论.     

风险投资分段投资的单合同最优激励模型研究

针对风险投资分段投资存在的道德风险问题,运用委托代理理论,建立了单合同的风险投资家和风险企业家之间的最优激励模型,模型对单合同的最优激励报酬进行了优化,并给出了风险投资的最优合同安排和最优退出时机,使风险投资家和风险企业家博弈达到均衡状态.最后,给出了一个简单算例.     

科技投入的博弈分析模型

本文把博弈论应用于科技投入分析,利用博弈论的委托—代理理论构造了一个委托—代理激励模型,研究中央对地方科技投入的激励机制,并针对委托人和代理人的不同风险情况进行了分析,讨论了对地地方政府科技投入激励的必要性。     

促销努力成本信息不对称下供应链回购契约

在由一个供应商和一个销售商构成的二级供应链,假设市场需求受到销售商的促销努力水平的影响,销售季节到来之前,销售商根据促销成本和收益决定最优促销努力水平和订货量。在促销成本不可观测时,利用委托代理理论研究信息不对称时如何通过回购契约揭示真实的促销努力成本。研究结果表明销售商有动机将努力促销成本报高,为了吸引销售商显示真实的促销努力成本,供应商必须付出额外的信息租金,随促销成本增大,销售商通过虚报高成本获得的利润减小,故需要揭示真实成本信息所付出的信息租金随之减小。由于信息租金的付出,导致了非效率现象的产生,使得销售商的最优订货量和促销努力水平均小于完全信息下系统的最优水平,只能得到帕累托改进的次优结果。     

考虑溢出效应的纵向合作广告契约

为研究经销商间广告溢出对供应链成员广告决策的影响.运用委托代理理论分析了考虑经销商广告溢出时制造商和经销商纵向合作广告契约.研究发现:信息不对称下的制造商全国广告投资努力、经销商地区广告投资努力、广告补贴及制造商收益均次优;伴随广告溢出的增大,制造商和经销商均搭广告溢出"便车"降低努力水平,制造商提高经销商的利润分成、降低广告补贴.不论信息对称与否,广告溢出的增大都能提高制造商收益.还讨论了广告弹性对合作广告的影响.     

基于委托代理理论的医疗激励契约研究

医患之间的高度信息不对称性是导致医患矛盾的重要原因。现有研究基于信息不对称情况下医患之间的委托代理关系模式,针对可能导致的道德风险问题设计了不同的医疗激励机制,但是没有充分考虑医疗服务的不确定性和异质性。本文考虑医方努力的不同动机,提出二维努力水平的概念,以医患双方效益最大化为目标,对患方就医过程中的医患博弈时序进行研究,在医方具有信息优势的条件下设计了不同情况下的医疗激励契约模型。数值分析结果表明,医方的固定医疗收益、收益提成比例和二维努力水平等激励参数与医方努力产出的边际收支系数、医患双方的风险偏好程度以及随机因素的扰动程度等均存在显著的相关关系。     

The brazilian nut effect by void filling: an analytic model

We propose an analytic model of the Brazilian nut effect (BNE) that utilizes void filling as the primary mechanism behind the rise to the surface of one large buried intruder particle in an externally driven confined mixture with many small particles. When the intruder rises upward, it creates a void underneath it that is immediately filled by small particles preventing the intruder from sinking back to its previous position. Even though the external driving is only along the vertical direction, the small particles are able to move transversely into the void due to the Janssen effect, which postulates that the magnitudes of the vertically directed and transversely directed forces in a confined granular system are directly proportional to each other. The Janssen effect allows us to calculate the transverse speed distribution in which the small particles fill up the void and the temporal dynamics of the intruder particle in the vertically shaken container. We determine the time‐dependent behavior of the intruder vertical position h, its rise velocity dh/dt, and the phase (dh/dt vs. h) as a function of particle size ratio Φ, container diameter D_c, kinetic friction coefficient μ, and packing fraction c. Finally, we show that the predictions of our BNE model agree well with published experimental and simulation results. © 2010 Wiley Periodicals, Inc. Complexity 16: 9–16, 2011     

Single-machine scheduling with learning and forgetting effects

Scheduling with learning effects has been widely studied in the past decade. With the increasingly moving toward shorter product cycle times in many production lines, workers in this changeable environment must constantly learn new skill and technology. As a result, the forgetting effect might occur in these situations. In this paper, we propose a model with the consideration of both the learning and forgetting effects. We show some single-machine problems remain polynomially solvable under the proposed model.     

Selling to customers with both Veblen and network effects

For the products that provide not only intrinsic value from their functions but also stylish consumption experience, there often exist both Veblen and network effects. Some customers are more likely to purchase the product if fewer customers can afford it, while others might appreciate the existence of more peers. Focusing on these products, we study the market equilibrium under rational expectations. The optimal pricing and quantity decisions reveal interesting insights about the effects of such mixed consumption externalities.     

标度广义效应代数和标度效应代数的结构

研究了标度广义效应代数与标度效应代数的代数结构,给出了比较完整的结果.通过引入全标度广义代数的概念,本文证明了区间[0,1)上的标度广义效应代数和单位区间[0,1]上的标度效应代数完全由单位区间上的阿基米德余模确定,标度广义效应代数恰同构于全标度广义代数的下集.若标度广义代数满足局部有限条件,则它同构于实数加法群的子群代数.满足(S)条件的标度效应代数同构于实数加法群的子群代数和全标度广义代数的字典序乘积的子代数.     

NONRENEWABLE RESOURCE EXTRACTIONS WITH A POLLUTION SIDE EFFECT: A COMPARATIVE DYNAMIC ANALYSIS

ABSTRACT. In this paper, we present a nonrenewable resource model including environmental pollution as a state variable. The model is analyzed to identify some of the characteristics of the optimal paths. In addition, we present a numerical example on the basis of the algebraic solutions of our qualitative model, and identify some of characteristics of the optimal time paths for two sets of social costs of the pollutant. These results are consistent with the proposition of the previous literature that levying the shadow cost of the pollution stock reduces the consumption of resource; hence, it slows the accumulation of the pollutant in the atmosphere. One quirk in the results, however, is that extractions will persist longer in the higher pollution cost scenario. The costate variable for the resource stock is decomposed into a scarcity effect and a cost effect; and the costate variable for the pollution stock is decomposed into an undesirable abundance effect and a cost effect. Both of these, however, are cost effects.     

An improved continuum skin and proximity effect model for hexagonally packed wires

This work presents approximate but closed-form expressions for “effective” complex-valued magnetic permeability and electric conductivity that represent the effects of proximity and skin effect losses in wound coil with hexagonally packed wires. Previous work is extended by providing improved accuracy versus finite element results for effective permeability and by providing an expression for effective conductivity, which was previously neglected. These material properties can then be used in 2D/axisymmetric finite element models in which the coil is modeled as a coarsely meshed, homogeneous region (i.e., removing the need for modeling each turn in the coil).     

Single-machine scheduling problems with both start-time dependent learning and position dependent aging effects under deteriorating maintenance consideration

In this paper we introduce a new model of joint start-time dependent learning and position dependent aging effects into single-machine scheduling problems. The machine may need maintenance to improve its production efficiency. The objectives are to find jointly the optimal maintenance position and the optimal sequence such that the makespan, the total completion time, and the total absolute deviation of completion times (TADC) are minimized. We also aim to determine jointly the optimal maintenance position, the optimal due-window size and location, and the optimal sequence to minimize the sum of earliness, tardiness and due-window related costs function. We show that all the studied problems can be optimally solved by polynomial time algorithms.     

效应代数的表示

本文讨论了抽象效应代数的表示问题. 对于一个抽象效应代数(E,⊕, 0, 1), 如果存在一个Hilbert 空间 H 和一个单态射 φ:E →ε(H), 那么称 E 为可表示的且称(φ,H) 是E 的一个表示, 其中ε(H) 表示 H 上所有正压缩算子构成的效应代数. 给出了一些可表示的和不可表示的效应代数的例子, 证 明了非空集 X 上的任一模糊集系统 F 和Boolean 代数B_X 都是可表示的效应代数.     

Properties and Data Analysis of Order of Addition Designs with Conditions

Order of addition designs with conditions are widely used in experiments, but references on this subject are rather primitive. The paper gives the definition of conditional main effect of pair-wise ordering factor, studies the orthogonality of conditional main effects of pair-wise ordering factors, and proposes the model of order of addition designs with conditions. Finally, it gives the methods for data analysis through two examples.